OER Parts offers a wide selection of Oil Cap for your 1966 GMC K1000 Pickup. OER Parts offers 1966 GMC K1000 Pickup Chrome Oil Caps, 1966 GMC K1000 Pickup Deluxe Twist-On Oil Filler Cap, 1966 GMC K1000 Pickup Chrome Twist-On Oil Caps, 1966 GMC K1000 Pickup Chrome Push-in Oil Caps, 1966 GMC K1000 Pickup Billet Oil Caps, 1966 GMC K1000 Pickup Polished Aluminum Oil Caps, and 1966 GMC K1000 Pickup Logo Oil Caps.