KABOOM! when hitting headlights.....

Clean your bulk head connection. The load of the lights cut the main power to the ignition switch for a split second. . It will be the fusible link wire at the bulk head. They always get corroded due to the material they are made of.
When I take that puppy apart to inspect/clean....am I supposed to use diaelectric grease in there? I still dont understand that stuff. Is it for grounds only?