Since you're going with PA - Pro Style drivers, it's assumed you interested in SPL performance, emphasis not necessarily being sound quality. I assume that you'll be using passive crossovers for the tweeters?
What you did not mention is the impedance of the DS18 PRO-GM6B you intend to run. Ae you going to run four 4ohms in all for corners of the car or are you going to run dual 6.5s up front in either dual 8 in parallel to 4 ohm load or dual 4 ohm to 2 ohm load per side. Same with the tweeters, how are you considering the speaker configuration?