Dumb question, but how do you adjust these things? 1997 C5

If you look close enough you'll see the adjustment screw inboard on each light housing...

I know the torx provides for vertical adjustment but is there a way to correctly "aim" them? I guess the old garage wall method is the only way and I suppose putting them somewhere between the bottom of the low beam pattern and the ground is the best suggestion. Anyone have a more "scientific" method???

Yeah it's pretty much set by your preference... I did mine so it overlaps the bottom edge of the low beams.

The "garage wall" method worked for me. With the car somewhere between 15' & 20' from the wall turn on the low beams. Mark the wall at BOTTOM on the light pattern. Turn off the low beams. Then adjust the fogs to be somewhere between your mark and the floor. Matter of personal preference. BTW, I have real problems with night vision so I replaced the 899 bulbs in my fogs with 885's. The 885's give out 50 watts of light vs. 38W with the 899's. At 50 watts, they're only slightly less than the full low beam bulbs which are 55 watts, I think. That's a 31% increase. I see a noticeable difference. :cheers: