removing it, use a siphon. Work outside and avoid fuel vapor buildup. Before removing the bolts that fasten the tank to the car, unhook the hoses and wires that lead to the fuel tank. Be aware that the fuel hoses might retain residual pressure and hold fuel in their lines, so relieve the line pressure before unhooking them. Since you are making the effort to remove the fuel tank, consider replacing the fuel pump relay and oil pump switch while you are doing the job; these components tend to fail about the same time as your fuel pump. When the fuel pump is installed, put a little fuel in the fuel tank and check for leaks along the system after you turn over the engine. With the fuel pressure gauge, check the system levels again, and compare them against the Plymouth manual's specs.