Back from SEMA, but slow progress.
Had to grind the nut off the manifold stud, but the motor's out!
I haven't had a chance to look it over too well or clean it up, but I think it has brand new lower intake gaskets. There's NO grime on them like the rest of the motor. I don't think I'll have to swap them out.
I also found out that the trans is a GM rebuild with a 2010 date on it. Might be worth hanging into!
-Rob