You can get a low mileage late model LS1 with a T-56, harness, and computer for around $4500. For mounts and other bits, I recommend

http://www.hinsonsupercars.com

They are a tad slow in making parts, (only because it's a 2 man operation) but are highly renowned in the 350 into an RX-7 community. Also try:

http://www.torquecentral.com/forumdi...?s=&forumid=11