Your distribution of funds are highly misplaced. Spending an incredibly large portion for a fancy head-unit isn't going to yield some supreme SQ. There isn't any reason why any other decent head-unit won't do everything you need for less, and without any discernible difference. Personally I wouldn't bother with rear speakers as any decent front stage will be plenty loud for listeners in the rear. If you feel you must, then I would attenuate the rear speakers in regards to the front. As previously mentioned you don't need a capacitor, and it WILL NOT help. The current draw from any one of those amplifiers is more then enough to instantaneously discharge the capacitor of all it's reserve. All it would be doing is drawing power from the batteries/alt, discharging, and drawing again, etc. The high output alternator and battery reserve will be all you need. I've never used mechman, so no comment. I've used DC Power, and their alternators are awesome, but their customer service is severely lacking at times, and I wouldn't be surprised if it took them several months to get you your alternator. Sound deadening: SDS. That is a no brainer. Why would you buy that crossover for a component set? Sure you could use the speakers in an active setup, but if your planning doing an active setup then why not pick some drivers geared towards your goals instead of compromising. Why do you feel you need an EQ? I'm not saying you don't need it, but don't buy it for all the wrong reasons. The processor I currently have is awfully fancy with tons of flexibility, and I only have two slight EQ adjustments. The idea of having to spend a billion dollars on a McIntosh headunit and Focal Utopia set for SQ is pretty damn far from the truth. The end result will primarily depend on the installation, although that's not to say you can make any drivers work either.