GMPartsGiant.com offers the wholesale prices for genuine 1998 GMC C3500 parts. Parts like Wiring Harness Rear are shipped directly from authorized GM dealers and backed by the manufacturer's warranty. Parts fit for the following vehicle options. Engine: 8 Cyl 5.7L, 8 Cyl 6.5L Diesel, 8 Cyl 7.4L. Model Code: C3500 CAB CHASSIS 135.5, C3500 CAB CHASSIS 159.9, C3500 CAB CHASSIS 183.5, C3500 CREW CAB LONG WHEELBASE, C3500 EXTENDED CAB, C3500 REGULAR CAB.