Jack, thank you for the link. I’ve watched it through a couple of times, and I’m with Russ up until 13 minutes in. With the mods he’s installed on his machine, he can do things that I cannot. The situation I currently find myself in is that the beam strikes mirror 1 about the same as your second target picture. With nearly 80% of the beam in the center of my M1 target I’m going to call it good (for now). It is identical for M2, both close and far. At M3 the beam was about 2mm high and right of center (regardless of head position). After making a slight adjustment to bring it to the center, I now have a situation where the beam is centered with the head at mid-point, slightly low & left of that with M2 and M3 close together and slightly high & right with the head to the extreme right. It would seem that the beam is parallel to the X axis rail in the horizontal plane but is no longer parallel in the vertical. I’ve looked for this issue within this forum (and the internet in general) but have not found a solution as of yet. The laser is still functional, but I would like to fix this before I start swapping lenses or making other mods. Any suggestions?