MLD wrote:
....
... My question is does anyone know of a good
way to seal the apparent gap (not easily visible other than of course
the fuel leaking out) between the fuel line and the tank? I tried
silicone; but that does not appear to be fuel/oil-resistant (trimmer
is 2-cycle).

Try some epoxy-I fixed a leaky mower fuel tank with some.
....

At the possible expense of making a future replacement nearly impossible.

I'm w/ the other poster who recommended getting the proper fuel line
from the OEM.

Alternatively, depending on the style/shape of tank, etc., could
possibly find and install a bulkhead connector so could have the
external fitting.

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