I have pulled engine and trans many times. On both my K5 and Suburban. That was with a SM465 trans in both of them. It JUST fits, but it fits. Biggest problem is the pinchweld along the firewall, it snags the adapter on the transmission a couple of times.
I don't have an adjustable hoist point, but I wish I did. Would make it a lot easier. I will probably drop in my 383 and 4l80E as a unit as well. its easier to do the bellhousing stuff out of the rig. But that truck will have the front clip removed(lifted way too big to even remove the engine alone).