Me too. I have looked at both of these but i would like to build my own better, i was thinking about putting a 15 in the spare tire area but not sure how well that will work.
You would be better off selling your fosgates and buy a stronger 1 sub system. Ive installed dual 12 inch boxes in mustangs before but it can be alot of work. You will also have very little trunk space after.I do know of a nice 1 sub system thatis for sale thatwill hit hard. It is in the trunk of a 2002 mustang now. The box was made specifically for its subwoofer and also made to slide in and out of the trunk.