I would like to replace the grommet on my fuel tank on a 1970 Challenger where the fuel filler pipe goes into the tank. I think it leaks if and when I fill the tank full. I would like to do this without taking the tank out. I've taken the rubber cover off that's in the trunk that seals around the filler pipe. I can see and touch the grommet from there. It looks like it might be doable from there but I'm wondering if anyone else has ever done it. It would save a lot of time and work to not have to drop the tank. Thanks for any thoughts or help.