if you have any extra $ lying around, buy these, get them shippd to whom ever is doing your car, have them install and retune, you'll thank me later
Y I know theres only 6 injectors, call intense, Im sure they'll sell you 8, they have better spray patterns than the 42#s, and you wot have to worry about running out of injector anytime soon
, and they're only $40 more than a set of 42s (based on 6)
You may also want this
GMs are notorious for voltage drop, this hlps with it, not 100% it will work w/ your app, but someone @ intense will be able to tell you...