GMC Cab & Chassis C2500 (1989-2000) Am/fm stereo

1 2 3 4 RF (+) RF (-) LF (+) LF (-) 17 18 19 20 RR (-) RR (+) LR (-) LR (+) 5 6 7 8 9 10 GROUND PARK LAMP DIMMER ANTENNA OUT IGNITION MEMORY ANTENNA BLK WIRE BLU WIRE BRN WIRE CASSETTE DECK CTSY FUSE DK BLU WIRE DK GRN WIRE FUSE BLOCK (UNDER LEFT SIDE OF DASH) GRAPHIC EQUALIZER GROUND PARK LAMP DIMMER IGNITION MEM (DATA) DATA GRY WIRE HOT AT ALL TIMES HOT IN ACCY OR RUN LEFT FRONT SPEAKER LEFT REAR SPEAKER LT BLU WIRE LT GRN WIRE ORG/ WIRE ORG/WHT WIRE PNK WIRE POWER ANTENNA SYSTEM PPL RADIO CONTROL HEAD RADIO FUSE RADIO RECEIVER RED WIRE RED/WHT WIRE RIGHT FRONT SPEAKER RIGHT REAR SPEAKER TAN WIRE WHT WIRE YEL WIRE