Ed,
I replaced the one on my 1954 3600 and it was necessary to completely remove the filler pipe. You should be able to loosen the fill hose and vent hose clamps, wiggle the hoses down as far as they will go on the tank, pull the filler neck up ,and angle the bottom out towards the dash and then pull it down and out. Replace the filler grommet and reverse the process. It looks like it gonna be way more difficult than it actually is. I do not think it can be done otherwise. Hope this helps.
