Sell the Buick to someone that wants to spend the money to rebuild it and use that money towards whatever you decide to run.
That's the way I'm thinking. $200 to whoever wants it. Honestly up to this point I didn't realize how affordable the LS swaps are. There are a ton of L33s and LQ9s in yards close to me. There's a few with 90-100k on them, and they are $1000-1500 complete with harness and computer. I really like the idea of having fuel injection.