I will be very interested in the opinion of others, I'm not very savvy when it come to rusty tanks and what to look for,,, but,,,, Yah you knew that was coming,,,, but,,,, looking at what I can see my thoughts are, there is rust there that is just waiting to plug a fuel filter, and if what I see is only a sampling then there is a great possibility that there could be just one little spot somewhere that is almost rusted through, which in short time will become a leak.
Now how to fix that? well some have tried and been successful for a time, others have tried and had no success, but I will leave that up to them to tell the tales.