Save yourself the trouble and just spring for the Versalab. I used to STRUGGLE with alignment issues at every darkroom I used especially at the newspaper darkroom with 3 enlargers all different! The Omega D2 was the hardest and I made the mistake of thinking I could get the alignment better with the bubble aligner as well a series of bubble levels. I was a wrong 22 year old! Took me a better part of a week to get it as good as I had it. When I got a versalab for my own personal use I went back to that old enlarger and it took me less than 5 minutes to instantly see and adjust perfect. Best 145.00 I spent at the time! I think it's gone up but I still think it is worth whatever they charge now.
Its a good design and stays in its own alignment very well. It looks very simple which it is and think that's why it works well. I put a lithium AA cell in it and I struggle to recall if I ever changed it.