1968 Barracuda with internal gauge régulator

The terminal with the plastic cover near B and D is the regulated bus. Notice it does Not connect at all to the barrel connector and feeds one side of the oil and temp gauges. That regulator is not what I would use. The internal regulator in the fuel gauge must be bypassed to go this route. I would not proceed with what you are trying to do without some more research. Search this website harder and you will find the answer. Also get a good wiring diagram. I have posted one over and over.