OER Parts offers a wide selection of Valve Cover Components for your 1980 GMC C2500. OER Parts offers 1980 GMC C2500 Breathers, 1980 GMC C2500 Hardware, 1980 GMC C2500 Hold Downs, 1980 GMC C2500 Kits, 1980 GMC C2500 Spacers, and 1980 GMC C2500 Valve Covers.