I leave it all nice and bare, shinny. After bolting it up, I use liquid tape. Dielectric "grease" is used in the aerospace world (my world) to seal connector shells against environment or in the automotive world (my world) to seal spark plug boots and to be able to slide boot on and off. And it's used in many other similar places. If it was conductive, it would arc the pins of a connector or arc the spark plug to the engine metal. In all the ground connections we did on aircraft components, we NEVER put ANYTHING on the connection. Nothing is better than "intimate contact" as it's known. You can't "enhance" that on a bolted join! We did use internal and external tooth lock washers. Party on! (Wayne's world)
You do need to clean and redo grounds but if it started and ran already that way, I think you also fried something? Of course, all you have to do is trace the hot from battery to switch, coil, starter and see where it isn't.
