So, after the non-removable corners frustration, hammering, sanding rust, painting, cleaning rain-splash+dust grunge and replacing rusted screws, pics 1 & 2 are the result. Not too bad. The front panel is steel painted with satin-finish black. The bottom edge was rusty. I only had gloss spray paint, so the repainted bottom strip looks odd.
Oh well, I'm only trying to get the system working, not attempting to do an antique restoration. Rust-flaking paint has to go though. And couldn't do the whole panel without losing the texts.
This box is just an interface between the PC and actual mass spectrometer sensor head. Not much in it.
I consider there's a very low chance of getting schematics from the manufacturer (who still exist), so I won't even bother trying unless I get stumped by some circuit failure later. Also there is a lot of potential for the mass-spec quadrupole sensor to be stuffed, and I doubt I'd be able to afford a replacement.
The worst part is that I really have to open the high vacuum bits, to separate them from an unsuitable metal panel to which they are attached. Though there is an alternative - angle grinding the steel panel down to a size that fits my setup, with the mass-spec attached. I'm not keen on that idea. But then I'm even less keep on opening it. Incredibly difficult to achieve adequate cleanliness & avoid contamination for a high vacuum system like this. There are even bake-out heaters (removed) for the conflat joints in that top part. To boil off residual air molecules. One tiny spec of oily dust or fingerprint inside, and it's rooted.
Also 3 pics of the vacuum parts.
He really isn't, I can personally vouch for that.
http://oglaf.com/fountain-of-doubt/