I have a 2007 grand prix with a N/A 3800 with a few mods. its quick but i found a guy on craigslist selling his totaled GXP and the engine and trans are not touched at all. (Pics show) he says it still starts up instantly and everything. How hard would it be to swap my 3800 out and throw in the 5.3L V8 and is it worth the time/effort. he only wants $1800 for the whole car and i can part out the interior and sell it easily.