I was going to go the MS-8 route myself, but decided against it. Instead I picked up an LC2i and 2 way crossover. I have 2 JL 10w6's going in the trunk and i'll use the crossover to get mid bass out of the factory door subs.
Curious as to how your MS-8 turned out though
2013 Mustang GT, Track Pack, 3.73's,
Hotchkis springs, 18x9.5,18x11 Forgestar CF5's, Lethal o/r H-Pipe, JLT CAI, BBR tune, Hotchkis panhard, UMI LCA relocation brackets, BMR LCA's, MGW, GT500 strut mounts, KYB struts, GT500 ab's, Steeda motor mounts, NX plate
2003 Mach 1-R.I.P
2003 Mach 1-Procharged*SOLD*