There is no "plug and play" that replaces the Northstar engine. You would have to change the entire drivetrain, wiring, computer as well as some cradle modifications. Very cost prohibitive to do, also if you live in a place that has testing before it can be licensed it won't pass. Bet to stick with the stock engine.

You can fix the head bolt problem with aftermarket upgrades. Not cheap but it works.

you can fix head bolt problem by using a 2005 engine...cad fixed it twice and the 2005 worked