oh, and that plug goes to the rectifier. I was missing the airbox, and people want a lot for banged up ones, so i made one from a coffee can. I found a crappy chrome dress-up air filter (looks like for a 2 barrel) for about $9 at auto zone, then put some 1/4 20 threaded rod with wing nuts on both sides, and used an old Nvr dull Lid on the other side