I had a similar problem on my Beneteau
423. The leak was from the sender until. The leak ended up being from one of the self tapping screws. I replaced it with the next size up. I would have drilled out the ring with a bigger size but didn't have a drill at the time. Now that the leak has stopped I think I will leave well enough alone. Longer term that may mean another leak. The leaked fuel ended up in our bilge
. We sopped it up with spill pads. We also sent a few passes of bilge
cleaner down from the tank end to get rid of the fuel odor
We did notice that the leak happened when the tank was topped of to max capacity. Without the extra pressure from a full tank we didn't have a leak problem, even when healed over. You may not be so lucky, but keeping the tank down a bit from full may help you make it until you have time to repair.
You might check with the Beneteau
393, 423, or 473 groups on Yahoo. Those fittings and tanks
look like the same.