Go to the fuse block and find the orange wires coming off of it. this is connected to the dash lights. If you wire the aftermarket gauge positive wires to them, the aftermarket gauge lights will come on and dim with the dash lights. The same orange circuit also has a wire going to the radio that you can also tap into sometimes....
I would not try to "tee" the oil pressure output, just hook up the aftermarket gauge tubing to the oil pressure hole.
Why not try piggyback terminals. They allow you to "stack" the flat blade terminals...
