I'd like to swap a spoiler with the third brake light into my 85 IROC. Aside from the spoiler and the upper and lower contacts, would I need anything else? My car has the rear wipper, so is that problematic where the contacts are concerned--three of the four are in use? What about wiring? Is there a pigtail on the harness or is the wiring separate? Where does the brake light wire come through the deck lid?

JamesC