[Bmstd]

ray_mcavoy... you have become my wiring mentor and hero. You were able to help me connect the dots so to speak.

After much thought and common sense applied (or as much as I have to offer) i had come to the same conclusion knowing the original oil warning light and the e-choke light was getting its feed from same connection. I was missing the diagram to help me understand that. With your help, i was able to figure out which wire in the bulkhead to re-pin,,, and now the oil gauge provides a reading.

Now for the new question,,, When i shut engine off, the oil gauge stays where it was at last. Then, when I cycle the key to on position, the gauge tries to return to zero, but once it gets to the mark by zero, it then stops for split second and bounces to the 3 o'clock position and stays until i start the truck. I have rechecked the ohm readings on the oil pressure sending unit and do get a 0Ω reading with engine not running and do get 51 Ω reading when engine is idling.

To add to this, the original trucks wiring for bulkhead to the cluster (warning lights) is lacking an additional 12v positive lead and and addtional ground lead. I ran extra lead for ground wire and used the bulk body ground terminal on drivers pillar (under dash) as ground source. for the addtional positive lead for now I jumped power from #3 location at cluster to #6.

Is this a case of damaged oil pressure gauge or possible wiring (ground) issue?

My goal is to go to local salvage yard and pull all the correct color wires with correct terminals from a donor vehicle and add to my existing dash harness. I am a bit OCD when it comes to doing conversions and want to have this correctly wired as GM would have done. I will be pulling and adding a single pink/black for 12v positive, black for ground and dark blue for e-choke light. This just sounds more simple that pulling a whole harness from an original gauge truck and swapping into this one. That and there are plenty of gutted out truck with dash wiring left.

1.) Please let me know your input and thoughts on the oil gauge still returning to the 3 o'clock position when key is on?
2.) Also would it be possible to send me a copy of wiring diagram and pin position for wiring at the bulkhead and fuse box so i can also make sure all my pin positions for both positive and negative between bulkhead, fuse box and cluster are also in correct positions? I want to leave nothing to chance.

I greatly appreciate you help to this point and really like these types of challenges. When all is complete, i intend to write this swap up for the forums so other do not need to go through this much searching again.

Thank you!!!