[Gixxer711]

I have a 2007 Avalon with the JBL system. Current speaker locations are center channel, A-pillar tweeters, front doors up to 6.75 or 6x9 and rear doors up to 6.75. I want to bypass the the stock system including replacing the head unit. Anyways, I have a Kenwood 60x4 amp and I am trying to get the best bang for the low to medium buck install. What should I do in what locations? Replace all four door speakers with co-ax, components with woofer in front door and tweets in pillars and speakers in rear doors, components with tweeters in center location bouncing off windshield with speakers in front doors and rear doors, no speakers in rear doors at all and so on and so on?