Instead of spending a bunch of money on a Northstar throttle body, I am gonna try to find one at one of the local yards. I just need to know which Cadillacs have the one I need.

I have a series 2 L67 with a gen 3 M90. I won't be installing it until after I port the charger and upgrade the cam. I just want to get it now, before they get harder to find (maybe). I'll look into wiring later (MAF etc).

Also, where do I find an adapter to bolt it up right?

As far as where to buy the adapter I got mine at zzperformance.com, I believe most like to use the 2000+ Northstar throttle body. As far as which cars I just pulled up a list using Wikipedia, to list a few Cadillac DeVille, Cadillac Seville, Cadillac Eldorado, Pontiac Bonneville & Oldsmobile Aurora.