I am replacing my aftermarket stereo in my convertible mustang gt (cobra clone) I have 6 new speakers for my car (unplugging/removing the mach tweeters, unless i can run those off the aftermarket amp) and hooking up a set of 10" subs in the trunk. is here any upgrade sugvestions to remove rattling and increase the stereo sound? I removed the stock amp in the car and will have Bluetooth/alpine deck and nice new speakers. Will i find an improvement if i spend the $155+ on a dynamat kit for behind the speakers etc. i hate how many rattles this car has! I want a sound/tight/built car! thanks for any input/advice.