I bought new electric wire harnesses to replace the two original 50 year old harnesses that are mounted on the firewall in the engine compartment . My car is a 1966 Mustang convertible, with 200 cu. inch 6 cylinder engine and C-4 automatic transmission. I am the second owner of the car. While comparing the new harnesses to the old ones before I removed the old ones from the car I found a difference in the harness mounted on the firewall that is to the left of the brake master cylinder. Both harnesses had the same color 8 wires coming out off the firewall but the new harness has a small 6" yellow wire down the line in the connector that plugs into the voltage regulator connector. This small yellow wire has a black female connector on the end of it with a tag on it that states, "This connector is for connecting the radio noise suppressor only, etc" . My car does not have a radio noise suppressor. It does have the 6" yellow wire that comes out of the connector that plugs into the voltage regulator but someone, obviously the previous owner, had spliced a black wire on to the end of the 6" yellow wire and ran this black wire back to where the main harness comes out of the firewall and then spliced it on to the black wire with green stripe located inside the main harness and then covered the splice with black electrical tape. I had never noticed this before. I found out that if I disconnected this splice all the electrical items in the entire car were dead. Absolutely no power anywhere but when I reconnected the spliced wire all electrical was restored??? I'm afraid to remove the old wiring harness and plug everything into the new harness because of this situation.
My question is if I purchase a radio noise suppressor and mount it at the voltage regulator where it should be mounted and then plug it into the new harness connector for it and do away with the old black wire that was spliced on to the old 6" yellow wire and to the black and green wire inside the harness, will I have full electric power.
If the car, when new had a radio noise suppressor on it I wonder why the previous owner, who by the way is now dead, would have taken it off and spliced in the black wire like he did.
I apologize for this long post but I don't know very much about electrical items in my auto or how to test them and felt like some of you probably know the answer to this puzzle. Thank you in advance for your help!