Erik
I read an article about carefully cleaning/lifting tank stickers in one of the Vette magazines some time ago. I'll search for it and see if I can find it. I would think someone around here might know, though. As far as your emty tank, sure, it could go if exposed to an ignition source, but so could an empty gas can.
Tony
I've looked for mine from the filler neck area, and with an adjustable mirror from below, and can't see anything either. I think I would have seen something if there was even a piece of one left. I think it's usually to the right of the filler neck, but have been found on the left side as well. I may drop the tank someday, but for the reason of cleaning up and detailing the frame, mainly. I have no "paper" documentation, but have the owner history back to 1974, and am confident as to my car's originality.
Dick