Hi John,
you're best off taking it to a garage and letting them do it with proper equipment, but if you insist!
level surface,tires correctly inflated, 10 m away at a right angle to wall
draw a horizontal line at the same height as headlight centers
draw a vertical line corresponding to center line of car
mark points either side of this, on the horizontal line, corresponding to the headlight centers
switch on main beam and check maximum illumination coincides with headlight center marks
take it to get checked out properly using the right equipment!
sure you know this but if the brass screws are stiff and you're starting to round them off, use a Junior hacksaw to cut a new slot. worked fine for me a few years ago
