I have done this on my 82 aircooled.  Mine has the larger filler neck
hole.  I first removed the filler neck.  Then I was able to reach one
hand over top the frame and down between the frame and tank, and
partially fitted my other hand through the filler neck hole in the
frame.  I was then able to remove the old grommet and install a new one.
 I used a small amount of vasoline around the outer and inner sides of
the new grommet to make things install easily.  Was a bit nervous about
pushing the grommet all the way through and dropping it into the tank,
but that didnt happen; be careful.  Make sure you get the filler neck
lined-up properly on the reinstall; it can be rotated around and can
enter the tank at an angle and leak.  Check the position before removing.

dr

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>1)  Can the large grommet between the gas tank and the neck of the filler
>tube be replaced without dropping the gas tank?  (I know, I should have all
>grommets replaced and the lines as well and I will.......as soon as
>possible)
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