$430 ? You must be joking.........The highest quote i got was $250 and i thought he was ripping me off. Lowest i got was $140 with oil, coolant if needed etc. I ended up doing it myself, $80 for a.c.l gasket set and few other things. Took me a whole day though, its quite easy to do but takes time. The supercharger is even quicker to take off than the plenum on a N/A car. Shop around for quotes. Check first taht the leak isnt coming from the rocker covers, what are your symptoms ?