Just searched everything I could find on fuel systems but failed to find my answer. My 40 is a 1964 and I've installed an '86 2F (getting closer to turning the key!!!). It appears that the new 2F has a return fuel line but my early '64 tank is not compatible; it only has a “fuel fill” and a “tank vent”. What options do I have here? I've considered tapping the old tank with an additional nipple or "teeing" into the original “tank vent” to accommodate this return line but wanted to get the facts before I proceed. Any ideas?