Classic/Antique Car Repair: Headlight Adjustment, adjustment screws, headlight bulbs

Question
I need help adjusting the headlights on my 1981 Pontiac Trans Am that I am currently restoring. I just bought new headlights and new adjustment screws from advanceauto. I just need the correct measurements for adjusting them, like how far away from the wall, how low the should shine on the wall, etc.        

                          Any Help Would Be Appreciated,
                                             Chris

Answer
You really cannot do this with any precision yourself.  Depending on which state you live in, there may be state certified brake and light stations where they have the equipment to do this right. With those old style bulbs, the equipment is getting hard to find, so you'll have to call around to find someone who has it.  Big trucks still use those bulbs, so you may find someone at a truck stop that is willing to do that for you. The equipment fastens to the little glass bumps on the lens and uses that to align the aim.  They have a special flat, level cement area to work in, and a wall exactly 25 feet from the bulb to help align to the marks.

The best you can do is to park on a flat, level surface that extends forward at least from your back wheels forward to a vertical wall that is at right angles to your car, and straight in front of you, exactly 25 feet in front of the headlight bulbs, and then make marks on the wall for the centerline of the car (sight through the rear window and over a mark in the center of the hood).  Now, measure the distance between the centerline and each of the 4 bulbs, and mark those on the wall.  Measure from the surface of the road up to the center of the lights, and make an "X" exactly at the height of the bulbs and each of the 4 bulbs on the wall.   Disconnect all but one bulb - I start with the inner high beam bulb on the left.  Aim that so that the bright spot is just barely below the level mark for that bulb, and exactly right on the mark for the left to right dimension.  Next, do the same for the right inner bulb.  Now, unplug the high beam inner bulbs, and plug in the left outer bulb, still with the switch on high beams.  Adjust it so that it's bright spot is touching the other left high beam pattern, but a bit lower and a bit to the right of it.  Do the same for the right side outer bulb.  Now they are all close enough that you can drive the car to a place with the right equipment to fine tune them without blinding anyone.  That's the best you can do.   Use the low beams only until you get them properly aligned.

Thanks for doing this - there are too many cars on the road that have misaligned lights, and it's a real problem for us old geezers!

Dick