Darin,
I am more than half way through my frame off on my COE. At first, I didn't want to touch the drivetrain because things seem to work OK, but a mechanic friend encouraged me to look into things closely. I ended up finding worn U-joints, damaged spider gears in the differential, worn axle bearings, leaking axle seals, damaged axle spindle, frozen (rusted) brake cylinders, etc. Many things were on their last legs, waiting for catastrophic failure. It was an old farm truck that was worked hard. Now I am glad I rebuilt everything.
I did not rebuild the engine because compression and vacuum were to specifications and the bearings were plastigauged and were also to specifications. I doubt I would put more than a few hundred miles a year on my truck, so the engine should last a long time. I cleaned, repainted and replaced gaskets, that is all. It is a later model 235 that the previous owner had put in the truck to keep it going. It probably doesn't have that many miles on it and I thought I might cause more problems if I had it rebuilt, not to mention the expense.
If your truck has had an easier life it might be OK just to clean and paint. Some things, like the drivetrain, can be accessed fairly easy later on. If you intend to have a daily driver, I would rebuild everything you can. If it is just for fun, do what seems right to you, given what your goals and budget are.
Kent
