I kept mine simple. Built a box to house a 10" JL w6, it fits between the seats and woofer fires down. I then built another box on top of it for storage and added cup holders etc.. Now I have storage and an armrest. Amp is mounted on top of sub box but under my storage compartment. Then I bought a cheap head unit and some 6X9s mounted them in boxes and secured to rear inside fenders under roll bar. Replaced old dash speakers and now have a great system especially for a Jeep. I purchased the amp and subwoofer on Craigslist and bought a cheap Sony head that came with 6x9s and 5" round for dash. I did it all for well under $250.
Round Rock, Texas
1981 CJ7 AMC304