I finally got to do a bit more today.
I made new brake lines for the rear axle and fitted them. They are very different from the originals, but they hug the axle housing and so should be less likely to be hooked by scrub and sticks.
I fitted the rare earth magnet to the diff plug, refitted it and refilled the rear diff with oil. I pulled the diff breathers apart to clean them but found that they have a light spring and a little plug inside them,
that has totally rusted away. I think the idea is that they keep the diff sealed until it builds up to around 0.5psi, then allows the expanding air out.
I had a bit of a think about it and came up with a better idea.

I got a 1/8" NPT barb to screw into the diff and clear plastic tube that I ran up the nearby brake line. On the open end, up under the chassis rail, I fitted another barb with a sintered brass filter on the end. This should let it breath and also keep the mud wasps out. It's all neatly clipped up to the brake hoses with cable ties so should be ok.
After that, I sprayed some degreaser around the diff and power divider, as they have layers of caked on grease and grime. I left it a bit to soak in then gave them a blast with the pressure washer. A lot came off but there is a lot left. When the ground dries out a bit I'll get back under and scrape and chip at what's left, then give it another go with the degreaser.
While under there, I realised that I am going to have to lift the tray off. There is a layer of rust between the chassis rail and the spacer rail under the tray. It looks almost like when a layer of ply delaminates. Once I get a fuel tank back on, I will start it up and try to find a level spot out the back. I will remove all of the U-bolts holding the tray down and then jack it up and sit it on drums and packing, then drive out from under it.
With the tray off, I will be able to clean the chassis rails and get at the brake lines much more easily.
With the ground under the back of the truck all wet, I decided to do something that I have been avoiding for a while. I got under the front and tried finding the engine number. The F1 User Manual says that it should be on a flat area on the right side if the engine, just under the air compressor mounting bracket. They lied!
I scraped and brushed everything I could get at, and after getting covered in grease and dirt, I finally realised that there was nothing there. Unless it is actually on the block
behind the compressor mounting bracket, there is actually no room between the bottom of the bracket and the sump pan that would be wide enough to stamp a number.
While cleaning crud off, I
did find a rebuild plate. That was pretty exciting.

I managed to get a fairly decent pic of it too.
After that, I thought i might just as well check the regular place for an engine number, down on the left side of the engine on the top face next to the oil filter pressure bypass adapter. Yep, there it was.
With a bit of degreaser and a scrub with a bronze brush, I got the pic below.
As you can see, it is 6 - 283 - 05317.
Now this is where it gets interestinger.
The REMLR list shows my truck, chassis number ADE 6X6 3588, as being a 1972 Truck, Cargo, 5 Ton, GS, With Winch. It's engine number is listed as 6 - 283 - 12376.
The plate in the cab agrees with the chassis number and that it is a Truck, Cargo, 5 Ton, GS, With Winch, but it insists that it is from 1969.

I searched through the REMLR lists for the engine number and found it was from a Truck, Dump, 5 Ton, GS, With Winch, so an F2 from 1968 with chassis number 2321.
So nowhere on my truck have I seen anything about it having the Abbey Crane. From what I can work out, it must have been a regular F1 Cargo and had the Abbey fitted while in service at some point. It has the little ladder platform for servicing and all of the operating instruction plates on the roof, even if they are so faded that I can't read them, and the lifting weight limit plate in the cab. At some point I am going to need to find out how to actually work the thing, so I can see what needs overhauling.
Earlier in the week, I had a play with one of the wheels. It seems that between the 2 trucks, I have 6 galvanised rims, so they are all going on this truck.
The first one I picked out held air, but had this weird patch on the side wall. There are no signs of any problems on the inside though.

Looking at it, it seems to be like a large blister. I was able to poke a screwdriver into that little hole and wiggle it around. It went in over 2". The rubber is soft to the touch, almost like silicon.
I looked up a few Youtube videos on changing tires on 3 piece rims, which were somewhat helpful. I took the valve stem out and let it go down. Next I applied lubricant to the bead. This was actually just laundry detergent that I had dissolved in a bucket of water to soak one of my weekend work shirts in, as it got covered in smelly gear oil. I remember removing a tire with Allan, (Red Rocket/Restless Rover), years ago and we used a short section of angle iron on the tire, against the steel edge. Then we belted it with the sledge hammer to force the tire down off the bead. It took forever as you had to chase the bit of angle after every swing. In the videos, they used a tool like a sledge hammer but with an edge like a curved, blunt chisel. They swung it and hit the tire right on the bead edge, without belting the rim. I doubted my accuracy, as I can't hit the same spot twice with an axe, so I tried a modification. I didn't have one of their tools, but I had a mattock. I put the edge on the bead, against the rim/lockring, and belted the spike on the back of the mattock with a 4lb mini sledge. Surprisingly, this worked. 2 good hits and the tire slid off the bead. I worked my way around and the outer ring dropped down. With that down, I was able to hook out the lock ring with the tire levers and worked it around until I could pull it off. With that and the outer ring off, I turned the tire over and tried breaking the bead on the back. That was a waste of time. The rim is held up off the ground by the tire, so it can't come free. Eventually I remembered one video where he had made up a stand from a smaller rim that he dropped the tire onto. I borrowed a rim from work and tried that. With the truck rim sitting up off the ground, it only took a few hits on the mattock to have the tire slip free.
From there, all I had to do was stand the tire up, pull out the tube protector and tube, and the main part of the rim just fell out onto the ground. Easy, just strenuous as everything weighs heaps.
I pumped up the tube to see what sort of condition it was in and found it had a single patch and an area where they had roughed it up to patch and then realised that they had missed the hole. It stayed pumped up all week, so should be ok to reuse.

I gave the rim and rings a good going over with the wire wheel. There was no rust, but there was a lot of rough sections, especially around where the lock rings go and on the other side where the tire seats. I think a lot of it was a mixture of dirt that got forced into the gap and rubber that came off the tires over the years. There were places where I think the paint was 5 layers thick.
With it all cleaned off, I primed it and it is ready to go back together. I have to pick out a decent tire from my collection and once it's all together, I will paint all visible areas with the olive drab, just like it used to be.

While the mattock worked, belting it with a sledge hammer was a bit rough on it. I have to clean up the edge with the grinder before using it again and the main blade has sharp edges that could cut the tire or gouge the rim.
I chased around and found the tool in the pic below.

This weighs 4lb and is specifically designed for breaking beads and being flogged with big hammers. I also brought a stump home from one of my harvest operations, and will reshape it a bit to make getting tires off a bit easier.
Next job is to take the toolbox off on the passenger side. With that off, I can clean the outside of the chassis rail and repaint it. After that, once I get another rim & tire cleaned & changed, I can fit them on the passenger side and then do the same to the driver's side. Then clean up and refit the fuel tank supports, fuel tanks, and the stone guard under them.
I got the second tank back from the radiator repairers.

I'm not really happy with the finished look. They cut out the rusted section and patched it, but they wrapped a strip of flat bar around where the tank restraint strap lays. They didn't clamp it flush to the tank surface before welding it, so it is up and down all along the length of it and the welds are really rough. I am going to clean up all the welds and repaint the whole tank, to match the other one. I might look at using wider tank restraint straps and insertion rubber to cover the ugly strip.
Oh well, that will do for now. With Xmas coming up fast, I am hoping for some good weather during my time off, to get plenty done. Will post here as things happen.
Greg.