REAR MAIN SEAL (NEOPRENE) - This seal can be used in place of the rope seal. It is easier for the novice to install, and those who have installed it have had no problems. The "wings" must be cut off with a razor before installation. In addition the rubber side seals and pins from the Rear Main Seal (Rope) Kit can be used to seal the sides of the rear main cap or RTV can be used to seal the sides.