It turns out that the pressure plate for the transmission is not normally stocked by any of the parts suppliers, but I located KMP Engineering where they are in fact manufactured. Martin sent me a complete clutch pack assembly with a new pump and cover. Now I will install them and reassemble everything.
Work this month was consolidated into 1 week, where I assembled the transmission with the new clutch pack and installed the powerpack again into the truck.
The wheels still did not move, so I bought a pressure gauge that would go high enough and checked out the pressure at the filter housing, finding it marginal. So out came the engine and subframe again, where I pulled the engine off the transmission and inspected things, finding some dried o-rings and a misplaced tube in the converter housing.
Then adjusted the bands to about 2 mm of play, double checked the connections in the governor and kick-down sections since they are visible from the top, and reassembled everything.
In the process of these three engine installs, one of the steel plates of motor mount came off, so not having a nearby supply, I glued it and put six stainless screws into the rubber. Still moves around as it should.
Then I put the engine back in the frame and pulled everything up into the body again, reinstalling the radiator, wiring, exhaust, oil filter, starter, etc.
Then filled it with 7 qts of 10W-40 MA2 Motorcycle oil for the best wet-clutch operation.
Finally with the engine running nicely, I finished the wiring of the dash and installed it along with the new switches on the steering column.