Fuel pump details

I wouldn't. I would remove the pump, make sure to pay attention to the lines, there are only 2, but you need to put the pump back together in the same position as you removed it. Clean it, take it apart carefully, keeping everything neat so you can find everything to reassemble in the reverse order you took it apart, You should check the pump to make sure it is working before you return it to the engine. with a new gasket between the pump and the engine
You can put a rubber hose on the suction side and put that in a gas can with gasoline and pump the fuel pump by hand,it should pick up the fuel within a few quick pumps. If so you should be in business.
My 2 Cent
K Clark

I now have a replacement diaphragm coming for the fuel pump on my 812. Can I simply remove the top from the pump and drop in the replacement diaphragm without removing the entire pump assembly from the car?