No, I've replaced the flex plate by sliding the th400 and NP208 back on long 3/8" bolts, of course after disconnecting crossmember, driveshafts, lines, linkage etc.
I respectfully disagree. I've done the swap and had no clearance issues with either the automatic transmission or NP205 transfer case. There are no geometry or linkage problems. The truck is at a friends house and pictures can be provided if needed.
If your truck has a top load shifter you may have clearance issues. I've done that swap but with a column shift automatic. No problem with the transfer case shifter.
I pimped out my mid 80's CUCV and replaced the indicator lights with silverado gauges. I used a multimeter to figure what each pin on the male plug did, then followed the copper leads on the printed circuit and matched them up. De-pin one lead at a time and label them especially if you're color...
I am not an expert, I'm pretty sure you need to have the angles of the pinion and transfer case output cancel each other out. Maybe check the google machine.
I am not an expert, I would think the wheelbase would be more important than the number of tires. Pre-bent lines can be tricky to install unless on a bare frame and the longer ones are sometimes bent in half for shipping. Why not buy or rent a flaring tool and coils of tubing, it is a DIY project?
Could try swapping out the dipstick with a vacuum port plug and hose clamp, could just be a bad dipstick seal plus a blow by issue. Maybe pinholes in the tube?
I'm on a pre 1960 "oldgmctrucks" website. One of the members MacGyvered up a 4 on the tree with reverse a separate lever thru the floor. For the most part we run inline 6's with low HP and torque.