I've got some LED windshield nozzles that I would like to wire to the parking lights but I want to go through a toggle switch so I can turn them off. The wiring needs to go through the firewall to the switch. After drilling a hole through the wall, is there any type of grommet or rubber piece I can use for a clean looking passthrough? Also, once the connection is made from the nozzles, through the firewall, to the switch, can I tap into the parking light wire on the inside of the car or do I have to tap into it at the light and feed all the way back through the firewall too. It seems that I should be able to feed it from the big 'ol wire bundle inside. I just don't know which wire would be the parking lights!!