i went that route. be prepared to spend 3k in suspension and bracing alone. the kit to drop in a LSx series engine is another $1200. your cheapest setup would be a cammed LS1 with exhaust which would be at least another 3k. You will need a beefier rear and with custom drive shaft as well, about 1k itself.If you go the LS2 route they are setup for a drive by wire configuration and are a pain in the ass to setup and about twice the money. I chose to go LS2 because out of the box 400hp/400lbs. But my car was already handling 400rwhp and i knew that it would hold. so with all of that being said, if you really would like to go that route then i'd be willing to lend you advice and help. it isn't going to be cheap unless you make this long term and wait on good deals.

good luck with your build, any questions just post it up.