I've read several posts about this and someone alluded to checking the connection to the relay panel in the left rear fender in the trunk.
Besides the 7.5a Fuse #31 on the dashboard side panel, is there anything I should be checking like a relay or other fuse or anything?

So far I have checked the wires physically for signs of wear or breakage, pulled out the trunk harness, cleaned and retensioned the bulb sockets,inspected the wires going through the trunklid ( should I take that hard plastic tube off the trunk hinge if it looks ok externally?) and I still haven't found the fault.

Also , since it's illegal to drive at night without license plate lights, is there a place I could tap into temporarily to run the lights until I find the fault? Or if I give up...lol ( since there is no bulb warning light for these)