Don't worry about staying mechanical, some like myself prefer the simplicity of the stock fuel pump.
Try to find a decent one, unfortunately many parts stores are pushing Airtex which is complete garbage.
It's a pretty simple process, you will spill a little diesel, but not a lot.
1) Remove the fuel lines. Plug the rubber line from the tanks to avoid fuel loss from the tanks. (It's a good idea not to have the nose of the truck pointed down as in backed into a steep driveway.) Check the condition of this short rubber hose that connects the fuel supply line to the pump. If it's cracked and/or stiff it's a good time to replace it.
2) Remove the two bolts that hold the pump to the block.
3) Remove the pump paying attention as mentioned above to the position of the lift arm.
4) Clean the surface of the block of old gasket material and sealant.
5) Install new gasket with sealant.
6) Position pump with the arm on the cam lobe. Install bolts.
7) Hook up fuel lines.
8) Start engine and check for leaks.