Stereo Harness question

im wokin on my friends laser and so far i have replaced the PS pump, windshield, extensive body work to both fenders, the bumper, and the hood, new interior speakers and the works...but the only thing keeping my from finishing the job is the stereo. every time i hook up the speakers they sound like crap. we ran the speakers on my head unit and they sound fine..i used his head unit to run my speakers and it sounds amazing (infinity perfects ;) hehe) now i think i am doin the wiring wrong and i dont have time to mess around wit it anymore..so if someone could kindly post a wiring diagram or just tell me what goes where it would be great! later

did you use the factory wiring harness. if so try switching +and - they could be switched if there hooked up backwards they will sound like crap.

they r hard to find but there is a wiring kit made for the stereo that says what wires r what. 5 or 6 bucks wal-mart or any parts place