Got it all finished up last night. Had to remove it to size the bushing for the switch. I used a reverse light switch out of a late model Mustang. Perfect depth but the neck on the switch is smaller than the hole in the shifter. The boot was full of damp muck probably because dirt had plugged the drain holes.
Accessing the nuts through the engine cover really isn't too difficult if you must do it without help. Less than 3 hours start to finish including cleaning out the muck and painting the base.
From under truck;
1. Mark 3 wires if wire tags are unreadable.
2. Remove one cotter pin and washer from shift rod and same from range selector rod at bottom of shift levers.
3. Disengage rods from shift levers and note which rod goes to which lever.
From inside truck;
1. Remove engine cover.
2. Reach through engine access and locate four nuts attaching shift mechanism to floor. Hold nuts with 7/16" wrench. There is a flat washer above each nut that is easy to drop.
3. Use ratchet and 7/16" socket to remove four bolts attaching shift mechanism to floor.
4. Carefully pry between floor and shift mechanism to loosen shifter.
5. Once loose, tilt shifter toward passenger side and raise shifter from floor being careful to avoid scraping neutral safety switch wires and shifter boot.
6. Carefully slide boot from shifter. Boot is very easy to tear.
Clean and lightly lube moving parts inside shifter.
Unless using correct reverse lamp switch you will need a bushing. Available from some military parts suppliers. I made one buy drilling, tapping, and cutting a bolt to fit.
When reinstalling shifter, again be very careful sliding shifter through hole so as to not skin wires or tear boot.