OER Parts offers a wide selection of Body Panels for your 1989 GMC R2500. OER Parts offers 1989 GMC R2500 Cowl Panels, 1989 GMC R2500 Cowl Drain Flap, 1989 GMC R2500 Side Cowl Panel, 1989 GMC R2500 Cowl Panel Plugs , 1989 GMC R2500 Cowl Drain Hose, and 1989 GMC R2500 Cowl Gasket.