I am currently doing the LT1 upgrade, and my reasoning is it was free. I live in CA and the Firebird wouldn't pass smog without a lot of work, so I bought a 71 Datsun that;s smog exempt, and now I have a use for the LT1! The LT1 has it's problems with the optispark, and it's horrible placement behind the water pump. I would like to point out the new Corvette Stingrays are using an LT1 again! I haven't looked into the possibility of parts from the new LT1 bolting onto the older ones, but I'd like to think at least some of it will. The LT1 is easier to come by in my opinion because everyone wants the LS1, so you'd have better luck, I got my firebird for $500 for the whole car, the car ran, but had a massive coolant leak and lots of problems. The 93 LT1 from the firebirds have a Oil Filter Cooler housing and that was cracked and also impossible to find (Thank god for JB Weld!!), so make sure to look for that, as they were not on a 94-96. The 97-02 had the LS1. I hope this info helps.