I'm guessing you've got a wire apart somewhere. On my Roo, they ran one wire back from the junction box that's under the left front of the frame (behind the battery) to the left tail light, then spliced in one wire up to the upper left rear clearance lights and one wire over to the right rear tail light. At the right rear tail light, they spliced in another wire up to the right rear clearance lights. (Ground wires similar.) The left front clearance light is spliced in at the junction box. At the left front clearance light, they spliced in to go up to the left top clearance and over to the right clearance and at the right clearance, they spliced to go up to the right front clearance light. They don't stick to standard wiring colors, so be careful.
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