92 or 93 Mustang Dash lights

My dad bought a mustang convertible last summer and the dash light are not working. The PO put a cd player in this car and the wiring is a complete mess. I know on my sisters oldsmobile when putting in the radio i read a wire wrong and lost the dash lights. is there any thing in the wiring for the radio that would do this on the mustang. It is just one of them small mustangs with the 4 cyl engine. any help would be apprieciated.

have you checked your fuses? also get a haynes manual they have awiring diagram in the back of them that will help you trace all of your wires.