Boswell, if this is on your 235 it's not that hard to change.
First, shut off the fuel, there should be a valve below the tank. If it's stock, should be a needle valve that screws in to shut the fuel off.
Next, disconnect both lines from the pump. Remember, when loosening or tightening tubing, use two wrenches. One on each side of the fitting, this keep you from twisting the tube or fitting.
After the lines are loose, you can attack the mounting bolts. Not the easiest, but it can be done with some wrench turning. Usually I will work on one bolt, then switch to the other. After both bolts are out partway, I will tap the pump to break the gasket seal. That will allow you to keep the pump pulled out from the block as you loosen the bolts, making it easier to turn the bolts.
I always figure that if I'm going to remove the pump, I just as well go ahead and replace it. Depends on what you can afford. You will need to either make of buy a new gasket. Gasket adhesive (not RTV) on both sides. The 216/235/261 fuel pump is almost idiot-proof to install. Put the lever in the hole, push it straight in, and put the bolts in. If you do get a new pump, you will need to transplant the pipe fittings, use teflon tape on them to seal.
