So my rear differential is leaking oil. I have never messed with the rear diff. It seems to be leaking on the side where the drive shaft attaches. Is this an easy thing to fix. Also i punctured a fuel line coming from the tank when i was sandblasting the control arm in the rear. There are 3 lines together and they are all really rusty. How hard are they to replace, and also is there a shut off on the tank somewhere so the fuel stops leaking.