the only thing i could think of would to be
taking the connectors for the rear signals with the green and black wires and removing the green wire from the male part in exchange for another wire that ends with two wires plugged into a second connector, like the one you gave a picture of, and then from the male part of that connector haveing one wire to the stock signal (green) and one wire to the tail light (blue or yellow)?
Edit: i attached a picture, does this even make sense? and am i allowed to separated a wire into two like that?
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