That is a nice press. The ultimate micros sure look sweet. There are lots of ways that the print station can get a little out of position. The print station arm can get dented by the platen clamps or the arms may have been used to move the press. The real trick is figuring out exactly what you want to do to fix the issue if it is significant. Be sure to check that the platens are flat and the stop on the registration gate is set right too!
You want to figure out if the off contact variation is equal along the length of the print station arm. If you try to shim the print station arm to carousel plate you are going to be tilting the print station arm. This can lead to a sweet spot at one point, but make the off contact tight on one end and large at the other. On my old Hopkins two of the arms were relatively true, but low. I unbolted and unpinned the print station from the carousel. With a platen installed I set them to a flat true piece of wood clamped into the print head (the wood was zeroed to the other correct level platens with no off contact). With a little help and some clamps it was possible to adjust the print station until I had the platen and "screen" relationship perfect. I drilled new holes and repinned the stations and bolted them in place. If I had just shimmed the print station it would not have been flat across the useable platen positions.
If the print station arm was not relatively level to the screen surface initially then shimming would be the way to go.
I have seen a press where a thin shim was used under the platen itself to fix an off contact issue. I chose to fix the underlying problem.
On one of the arms on my even older 4/4 hopkins I found that there was just enough play in the registration gate positioning that I could unbolt it and move it slightly to fix my off non parallel contact issues.
I really liked printing with my older hopkins after I got it dialed in. I'm sure your BMW will rock.
Plot your moves in advance. Good luck!
