OER Parts offers a wide selection of Body Panels for your 1976 GMC C15 Suburban. OER Parts offers 1976 GMC C15 Suburban Full Firewall, 1976 GMC C15 Suburban Partial Firewall 1976 GMC C15 Suburban Firewall Body Mount Patch Panels, 1976 GMC C15 Suburban Firewall To Floor Braces, 1976 GMC C15 Suburban Firewall Extension, and 1976 GMC C15 Suburban Firewall Delete Plate.