Chevrolet Repair Questions? Ask a Mechanic for Answers ASAP
None of those wires are ground. Ground circuits are indicated by Black wires going from the bulb connectors to the body and frame. If I may ask, what are trying to do/fix?
OOps... I guess I missed the part where you stated you were adding load resistors to compensate for LEDs. Sorry about that.
60 Watts is a bit much. A regular stop/turn signal bulb is rated at a little more than 26 Watts, so adding a 25 Watt resistor in series to each power circuit with the LED should do the trick - in series means you cut the wire and splice the resistor to each end.
OK. I see that you're using the type of resistor that needs to be added in parallel (see attached graphic). For that kind, splice one wire from the resistor to the power wire and the other to ground (Black wire). For example, for the Left Tail/Turn Signal lamp, the power wire is Yellow, Black is ground. For the Right Tail/Turn Signal lamp, power wire is Dark Green, Black is ground. The Left and Right Stop lamps each get a Light Blue power wire, Black is ground.
Park/Tail lamps each get power on a Brown wire, Black is ground.