Hullo. I'm in the process of converting my 83 Jimmy from sealed beam to composite H4 headlights. I picked up 4 convertors for $14 apiece. The low beams went smooth as silk, the factory harness plugged right into the H4 bulb but the high beams are missing a prong. Also I noticed that wires go to all three prongs on the low beam. I'm a little confuzzed.. being that I have 4 bulbs, I figured it's 4 single filament (2 hi/2 lo) and that since the H4 is a 2 filament hi/lo bulb with 3 prongs, that it's prolly one for ground, one for hot low beam and one for hot hi beam. If that's the case, why are there wires going to all three prongs on my low beams? I can't seem to find my volt meter so I'm in the dark. Anyone know what the pins on the H4 bulbs are looking for as far as +/-? Thanks.