Sounds like there may be other gremlins in the picture with the car stalling out (gas mileage isn't great with these old engines but 5 mpg?). I had the same thing happen to me with gas going everywhere 1 month ago when the bird was still on the car hauler; gas was dribbling out from up top of the tank. For me, it turned out to be a 2-inch id, 3-inch long piece of rubber soft line hose that had dried out and cracked. The hose runs from the fill point to the top of the tank. You can remove your license plate and check it out or drop the tank, replace the tank sender. Easy fix in the end.
Kevin-
Restoring and maintaining old cars and old boats....oh what fun we invent for ourselves. Seems to go in stride with ....You don't live it until you own it....Three steps forward....two steps back ....
