I want to do a complete overhaul of my factory system. The car is a 2005 GTO with a Blankput stereo. I'm not really sure what will fit though. I have 8 speakers. 2 tweeters in the dash, 2 under the rear window, 2 in the rear side panels, and 2 in the front doors. So the question is so I need 6.5's or 6.75's. Also do I need shallow mount speakers for the rear side panels? I have looked a 2 vehicle fit guides and they say different things. One says they are all 6.5's, and the other says they are all 6.75's. Can anyone help? I don't want to buy speakers and then have them not fit. Also any suggetions for specific speakers? I was looking at Alpine type R's, I can get a pair for 85 bucks. I am also going to later add subwoofers, but I want to do the mids and highs first. You guys always ask about budget, and I'm looking to be somewhere around 550$ for all the speakers and an amp to run them.