'77 2500 fuel filler removal

[jastx]

Here is a picture of my fuel filler from the inside. It's the small cap version. I would like to remove it and install the earlier, large cap assembly in its place. My car has nice original paint and I don't want to mess anything up, so I hope you can advise me on the steps to take to do it right and also answer a few questions.

- The black substance on the left is hard, not soft. Was this original? If so, what purpose did it serve? Is it covering something specific?
- With the tubes sticking out of the filler neck, the hole to remove it must be large, much larger than the grommet above the tubes. How do I remove the filler?
- Does anyone have a picture of the hole in the '77+ body through which this filler fits? Is it circular or does it have a notch, perhaps under the black substance, to make room for the tubes to fit through?
- Anything else I should know about this procedure?

Compared to the incredible chassis-up restoration work many of you do, this is small stuff. I appreciate your advice.

[oldgeebee]

You need to remove the black sealant to reveal a slot which will allow you to rotate the cap to get the drain tubes through.



If you have removed the hose to the tank and the black sealant then the cap can be rotated through 180 degrees with the cap in the open position - careful when you do this because the hinge can scratch the paintwork (see scratches in my photo!). This will allow the first drain tube through the slot then you need to turn it back through 180 degrees to get the second tube through.
On my 79 3000S the sealant was soft so easy to remove. If yours is hard then it may be a bit more difficult but its the only way to get the cap out.
GB

[jastx]

Thanks, GB. Exactly what I needed.