[Rallye72]

I looked in my shop manual, here's what I think you need to do to unscrew this:

As "Nut" stated: get the pipe (all of them, not just one - by the book) unplugged. Reconnect them via rubber hoses from the tank to the "vapor liquid separator" I'm assuming your mechanic didn't remove that device. There are (or should be 5 lines: one leads to the charcoal cannister, the others relieve the pressure from inside the tank from each of the top four corners of the tank. One of them (the shortest inside the seperator) serves as a return hose back to the gas tank. All of these lines are at different heights inside the seperator to account for parking angles and maneuvers. The tallest feeds the charcoal cannister which serves to "store fuel vapors from the fuel tank and carb bowl." You don't have to have the cannister, most folks took them off, but I think it helps cut down on vapor oders.

As far as your gas gauge I'm willing to bet he threw away the ground strap at the fuel tank. I've had this problem in the past and it was typically a ground issue. As far as the lurching I'd guess it's fuel starvation because as the fuel is sucked from the tank it creates a vacuum inside the tank that effectively prevents the fuel from flowing evenly (that's a guess on my part, there may be other reasons).

If you can't reverse the handiwork I think Nut is correct: you'll need another fuel tank. I also strongly recommend that you get a shop manual on CD for your car, mine has saved me countless times especially wrt electrical problems. Good luck.

g