Rear Indicator Lights

[Cracker]

Can anyone tell me how the upper three indicator lights are wired in on a 2000 Excella? I've checked the ground on all three lights and it's good. It appears that the positive side is dead. I've been hesitant to remove the light bases from the trailer shell because of the lousy weather we've been having. Before I do, I'd like to find out where the positive lead connects initially (--with respect to driver side, center, or curb side) and then how the other lights are connected thereto. Incidentally, the 2000 Excella 30 does not have rear upper clearance lights. This probably means that the positive lead "dead ends" at the upper three lights. I can't imagine any good professional way to rewire these lights if the positive is dead. Is there any chance that the positive originates behind one of the rear tail lights - and is within reach to check the connection?

Many thanks,