Hello the title pretty much says it all, Any tips on cleaning the contact on the top of the mod, that is where the battery makes contact? I can't seem to remove the contact so I can't easily rub it with larger things. My contact has little to no arc marks on it right now but I'd like to know how to clean it in the future if it increases. I've heard of using erasers or the rubber bottom of mouse pads. Any tips for this mod specifically?