There are adjustments for the headlights. If you look online you will find a lot of information pertaining to the headlights. One of the easiest things to do is to follow the linkage and see where it's binding up and then make the adjustments from there.
Loosen the 3 bolts on the bracket in front of the vacuum actuator (NOT the ones on the vacuum actuator itself) - the ones that locate the bracket holding the linkage with the springs and the clevis (remove the clevis to get at the center bolt). To remove the clevis, first remove the 2 springs that attach to the clevis pin, then the cotter pin and the clevis pin itself. The other 2 springs can stay attached.
3. Adjust the full open height with the adjusting bolt - the one on the arm that contacts the headlight frame when full open. Out is lower, in is higher. Use a long socket extension and a universal joint to reach the adjusting bolt through the grill opening. Make the bottom of the bezel flush with the front edge of the opening.
4. Actuate the mechanism by hand so you can feel the "over center" condition when the door is fully open and the linkage fully extended forward. Move the bracket until you get a slight interference fit - the linkage gently, but firmly, "snaps" forward into the over center position when you actuate it manually. Tighten the 3 bolts loosened in step 2.
5. Adjust the clevis by turning it on its shaft until the clevis pin (the rod that goes through the clevis, and where the springs mount) is all the way to the front of the curved slot it rides in. Remove the clevis pin and turn the clevis 1 to 1 1/2 turns counterclockwise to give a slight interference fit at the end of its travel in the open position. The clevis must extend enough to push the linkage into the over center position, which is what locks the door in the open position. The interference fit ensures this locking, and prevents rattles too.
6. Last step - adjust the closed position with the small hex bolt - this is in the center of the linkage, and points down at the ground when the door is closed. The hex is small - the same size as the diameter of the bolt itself. Adjust so the front edge of the door is about 1/32" inch lower than the front edge of the opening. This will minimize wind noise and water entry.
7. Test. The door should snap into full open firmly, with a click, but not a thud. If it makes a loud thud or a bang, re-do step 4. The thud means the over center position is too tight, and this will put too much strain on the linkage, damaging it over time.
Note: It goes without saying, but just in case, you should use a good lubricant on all pivot points and moving parts in the linkage."