Is there a way for me to change the position of the distributor case/vacuum diaphragm so it doesn't hit the oil pressure sending unit and allow for more adjustment of timing without throwing the current timing off? I hope that makes sense.

When I adjusted the timing the diaphragm hit the oil pressure sending unit and must have shorted out the unit cause the pressure gauge immediately went to H and won't come back down. I got a new unit and when the ignition switch is turned on it will stay at L. I can't seem to get the old unit out of the car to replace it with the new one but plugging the new unit in the needle went to L plugging the wire back into the old installed unit goes back to H so it must be the sending unit.