I found two factory 4 ohm 6x9's with bigger magnets than mine in a '97 grand prix gt none bose system. It also had two smaller speakers (im guessing they were tweeters) and the speaker grille had places for them too. Im wondering if the magnet size matters? If these 6x9's will work in my stock system? Is there a way to wire in those tweeters? Why would this '97 gp gt have tweeters and my '99 gp gt doesnt? Thanks, brad.