Wiring issues from previous owner
 

Bought my 92 w250 5 speed Cummins a few weeks ago and knew I'd have to fix some stuff on it. Previous owner for some reason had bypassed the ignition for fuel shut off solenoid and put that to a switch, and also put the entire dash on a switch instead of key on power.

I would like to return it to how it was factory but wondering if he did it for some other reason I can't figure out? I found two wires on the back of the fuse panel that had been cut and ran over to the switch instead of the steering column. I'm not too great with electrical so any help would be greatly appreciated!