As was stated earlier, I would look for another block that you can do all the work on. There is a moderator on here by the name of FormulaLT1 who just built a 383 stroker motor out of a LT1 and dropped it into his firebird. You could PM him and he could give you more specifics, but for all practical purposes the best way to do it would be some combination of stroker motor and some kind of power adder, wether it be boost or nitrous.
Rob