I can't really help you on that unit, but I used to repair laser disk players. This required a set of jigs to coarse adjust the beam, and then a jig to break out the optical sensor to a scope to fine adjust for max signal on the photo cells. Doing it on the fly is difficult, but possible IF you know the unit and did a lot of them. It's obviously a very, very fine adjustment.....
Can you find a manual at all?