I’m going to wire my 2 up seat into the factory tail light wiring.

I’ve been told that T-tap connectors work fine. But I’m not sure what gauge to use. What gauge is the tail light wiring?

I will be wiring a 4 pin trailer connector.

Just curious if anyone knows which wires are which? i’ve read enough to know that I could just buy a tester and probably figure it out, but I don’t have a tester and have never used one so i thought I’d just throw the question out there.

Is it true that one wire is tail light, one is brake light and one is ground? Making the 4th wire on the 4 pin unnecessary.

Any guidance/advice would be greatly appreciated.

Thanks
Tom