I've done this swap but it was many years ago. I just ran a wire from the sender to the backside of the gauge, supplied 12v and a ground. I think my gauge was from a 75 or 76 vette, bought the sender for same car and a 45 degree elbow to get it to clear some stuff and screwed it in there. Again, its been a while but I think I sent it to a resto shop and had it painted to stock '73 look, I may have swapped out the face but I don't think I did that. Never had any trouble out of it at all. I also was trying the mechanical to quartz clock swap at the same time. I definitely DO NOT recommend that swap. At least not from D&M restoration. All I accomplished with that was I lost my original mechanical clock and it cost me 60 bucks. My clock never has worked right or kept correct time. It sometimes actually runs backwards. I exchanged it with D&M once b4 my warranty period ran out but the next one also had the same prob's. Runs backards as much as forwards. It's really humorous to watch it. It acts schizophrenic, switches back and forth between forward and reverse erratically. At least its good for a few laughs.
Back to the oil gauge...
I could never get mine to quit leaking at the motor or under the dash. If you have a nice stereo in there then your risking oiling it with a gauge leak. My old gauge oiled my CD player once or twice. Just got tired of it. This is definitely an easy upgrade and a worthwhile one IMHO.
Why do you want to do it?
good luck
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