What engine do you have in it currently? If it's a 350, why not just get some vortec heads (pretty inexpensive),stroke it to 383 put a nice cam/roller rocker combo in? That would be a pretty stout setup, and I'll bet you could do it for less than you could do a LT1 conversion, given all the expenses. Just a thought.
yeah, putting an LT1 in a Non LT1 caprice is quite a task. the guy who runs www.bigfastcar.com did one to his, and hearing the headache that he went through made me decide just to get a '94 LT1. you have to get the complete cooling system out of an LT1 car, by lt1 car i mean b-body, wiring harness, and accessory brackets, if you try to use the existing brackets, you'll end up putting the AC in the frame, and you'll also have to get the full exhaust of another LT1 car, including the crossmember. if you're looking for performance, do what the other guy said, vortec heads, cam, rollers, you'll be happy. but that's just my .02 cents, you're gonna do whatever you want.
I have a wimpy 305 under the hood-right now im thinking my two options are to go full efi w/a LT1 or a buddy of mine has a 383 stroker he would part with, all carborated though. Appriciate the feedback-pls keep it comin.