Put in a Panasonic head unit and Polk speakers all around. 5.25" in the back, and i fit 6.5" in the front doors by drilling some new holes. Sounds far better than the stock stereo. only spent $300 for it all because the speakers were on sale.
http://www.polkaudio.com/
polk makes excellent component and coaxial speakers, very good sound in thier smaller speakers, i havent had any experience with thier subs tho, most people tend to go with the bigger names :dunno:
polk is a bigger brand, its just bigger in certain parts of the country than others and is really big in europe! i've always loved polk momo's myself i used to run 3 10" sub's with an MB Quart 1000w X 1@1ohm! i did some research and planned for about 3-4 months on the box and made/tuned my own, it hit 148.7 db at my first bass off competition! but i also buitl the box to react to the space within my xj! so i guess you could say the box was made for the speakers but tuned to the jeep! any ways polks a GREAT for home or auto and the momos are even better! just IMO stay clear of there amps, there great amps but the amount you pay for such small wattage aint worth it!