Awright kids, play nice...
Actually, any V6-60 from a RWD Chevvy will work - which means F-body (Camaro/Firebird) and truck (S10/S15 and similar.)
There is also the option to install a SBChevvy plant - Advance Adapters makes a bolt-in mount cradle to accept it. Get a 4WD THM350, THM400, or THM700R4 and transfer case, have your new shafts made, and you're there. You can also swap in a stick if you really want to - you've got a few options that will bolt up behind the SBChevvy.
Or, get really nuts, and swap in a SB AMC (304/360/390/401, I think) and keep it AMC - which means finding an AMC transmission that will bolt up - A727, A904/999, or even AW4 will all work - any transmission from behind the AMC I6 will go in behind an AMC V8 - they use the same bell pattern, as I recall.
This really has been done around pretty good - pillage around, and see what you can see. "The search button is your friend. Know it, use it, love it."
"Once you have pulled the pin out of Mister Grenade, he is no longer your friend." (Couldn't resist - needed a humourous antithesis to the previous comment...)
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