Slow progress with the valve body today.
It was DIRTY. Here's an example of the muck on the dividing plate.
There are mountains of crap all over it. Lots of the valves were stuck in place. I ended up cleaning what I could with brake cleaner and then leaving parts to soak in penetrating oil before using the shank - THE SHANK! - of a 6mm drill bit to pull the stuck plugs out of their holes.
I've come across more evidence of tampering - some of the slotted heads on the screws were burred. To avoid this from happening to you, my advice is to not use normal screw drivers but to use a bit and a 1/4" drive ratchet.
I've laid out all of the valve body parts (for the lower part of the valve body) on paper and taped them into their correct position with respect to each other and in the correct orientation - well I say correct they are as I found them.
Final tip for those of you who are going to do this job - when you've finished for the day - care for your valve body. Wrap it all up and put it in a clean cardboard box well away from your wife, partner, the children, your pets, other peoples' pets, the drunk neighbour etc
Next I'm going to take the next layer of the valve body to bits and clean that up.
Then I'll go through it all and check what's what with ATSG and the FSM. As I've found evidence of "someone there before me" I'm reluctant to show what I've found so far!