OK. Found the adjustment, followed the instructions in the FSM and FTM, and the truck now starts from "P" and "N" like it is supposed to, and park actually is park, not reverse. But I am still having issues with drive. It still acts like it is in neutral. If I put it into "2" then slide up to "D", it seems to be OK.
My current thought is this: either the adjustment is slightly off, so drive is just past the detent in the cab, or there is something else wrong that I haven't found yet.
So far I have changed the governer pressure sensor and solenoid, changed the fluid, replaced the filter, checked the TV cable (no adjustment needed), and adjusted the shifter cable/linkage. Someone at one point suggested checking something with the parking gear while I was inside the transmission, but by that time I already had it put back together.
Any other thoughts on what I should check next? I need to do the alignment either later today or tomorrow before I can take it out and test drive it to see if it eventually pops into gear if I leave it alone. I tried testing it from where I have it parked and it didn't seem to want to, but I would like to test it on a short trip before I declare that conclusive. If it does not pop into gear, I think I am leaning toward a misadjustment on the cable. If I understand it correctly, I can remove the spring for the button in the cab and eliminate the in-cab detent mechanism, then I would be relying solely on the detent in the transmission. If that works correctly, then I know the cable is as maladjusted as I am. Other thoughts???