About you want to use your stock transmission so you can yuse your stock transfercase. That makes zero sense.
I've got no plans to exceed the tow rating of 6500 lbs and have no plans to put tires larger than 34" on the truck, its my daily driver.
The 5.0 is at 200000 miles and getting tired so I'm looking to do something about that issue.The truck is in great shape and really like this body style over the newer trucks. I don't really want to put another 5.0 in it so I'm looking for factory dependability along with a little more power. I want the swap to be with parts from the same era truck (GMT400) so that the factory parts are available. Not looking to increase performance to a level that would require aftermarket parts just a good factory install that will do the job. I am partial to BB's as I do have a vette with a 496 (old style) and have had a few trucks that I swapped BB's into.
To me it is easier to keep the factory correct pats to the truck and have them built to handle the power if needed.
It seems with TQ management in play and not exceeding the limits of the truck the parts should live as long as they are in good shape.
Maybe I'm wrong and if so I'll deal with it then, I'm the only one that drives this truck and I don't dog it.
Neal