I have started converting the two fuel line pressured tank to a one line on a 1959 fd-13r 18hp johnson. Ive went the route of buying a mikuni pump. ive taken off the manifold and there are two flaps covering the holes. Ive plugged the one with a vacuum tip, and this is where my question comes in. Do i need to re-install the rubber flap over the existing hole, or does it matter. I havnt noticed this covered any faqs. So far all the pages have been helpful. Any advice would be much appreciated. Thanks.