Where is the Oil Pressure Sensor on a GMC 8.1 liter engine

I have an 88 Toyota Camry and the rear drivers side window won't go up but it will go down if I press the back window button. When I try to control it in the front, all of the panel lights go off and back on when I let the button go. Also, I've tried to locate the problem with my lights. Every time I put a fuse in and turn on the parking lights to light up the dashboard, the fuse blows. I've disconnected the yellow box and opened it, to find that a small wire that's soldered onto the board was messed up, so I know that has to be replaced. Checked all wires for any cuts and I don't see any. Will someone please help me and please..... I'm new to this "fix it yourself" thing and this is my first car so.... Simple language that I can understand would be helpful. Someone help me please?