Will these fit in my 350z....infinity 63.5 in the rear and alpines in the front?...help me out guys

 

I don't know about the Alpines, but I have 62.5i's installed in my rears. Very simple direct replacement install. The fronts are tricky with most speakers since you have to fabricate some type of spacer because most aftermarket speakers are deeper than stock. Do a search or browse around this forum and you'll see many examples of what others have done.