My question would be....where are you going to find the engine/transmission package without paying an arm and a leg for it. The Lexus LS400 first gen car is selling for $12,000 to $25,000, so even if one has been wrecked, somebody is gonna rebuild it to sell as a running car. It's only a 250 hp motor and where are you gonna find hop-up pieces for the trans after you bolt on a blower?

It's great to dream about a project, but I think you'd better think this through a little better before you start.