I'm at the point where I'm cleaning up my original (1980) rear wire harness. As I was cleaning the bulb holder sockets I found them to be caked with a beige, thick mastic type of material which I scraped out. My guess is the schmoo was packed in there at the factory to act a water seal/ vapor barrier. Do any of you kids have a suggestion for a workable replacement? I thought of smearing some dielectric grease in there but I don't think that's really the best product for the job.