I'm going to build a table for this one.
I've had a darkroom setup for years.
If you are handy, and I assume you are to attempt to build the table, you might wish to build something to replace the part of the base that is removable, with adjustable shelves, makes a nice system to larger prints, or consider wall mounting. We have one darkroom with such a set up, the base just pulls out and can be moved as you need. The enlarger just barely fits between the floor joists in my darkroom when it is raised. I use a kitchen base unit cabinet for mine.
I had the Picker Cold Light head, probably made by Arista, and liked it very much, but mostly I use the Minolta Beseler Additive Color head, somehow adding red is much more intuitive, and it is easily adjustable to .01cc or some crazy small unit. Color Bat used to offer parts and instructions.
I think the 45M series are the best of the Beseler line, have had one for a long time, no problems.
A down and dirty alignment check can possibly be made with a piece of old fogged film, you scratch it with a razor edge from corner to corner, and see if the scratch is sharp everywhere when in focus.
That said, the alignment tools are pretty precise.
Watch your head when you are focusing, or keep a cold rag to help with the lumps.
It can easily be used at 90 Degrees, but watch the top bits do not fall off when you rotate it, you should see the 90 degree lock for horizontal usage.
The manual was not very big, so do not worry if you cannot find one.
The lens boards were standard 1/8" thick (I think) aircraft aluminum, and can easily be made by a machinist friend, but if you hang about any real stores, the bits and pieces are lying about.
Doubt if you are going to wear it out. ;-)
Regards, John