Sounds like the building has been entered a few times. I still wouldn't admit to him that you went in there though since it's technically still "breaking and entering" even if the door is wide open. I'd probably do the same thing though if I knew the place wasn't being watched, though I'm always timid about going on other peoples' property, even if it appears unoccupied/abandoned. If I had more guts and went snooping in abandoned buildings I'd probably strike rich in vintage fixtures lol.
Typically when I get vintage lamps, they either come single or a matching pair if in a fixture (unless one lamp was replaced). If it's just one, it is saved. But if I have two sets of two matching vintage lamps, I'll pull one lamp from each set and use it in a fixture (provided they're the same color and phosphor mix) that way one lamp from each pair is saved. Or if I get lucky and get three identical vintage lamps, I'd put two in use and keep the third as a spare. That's how I'd do it if it ever came down to using my vintage lamps, though I'm going to use my non-vintage ones for now. When I get my own place I'll probably put some used vintage lamps in use on less-frequently-used fixtures. The ones I use all the time will definitely have "disposable" lamps that I can burn through without having a real loss.
Yeah a fuse wouldn't be a bad idea if you get this and decide to put it into use lol. Hmm sounds like it might be a top-access fixture, where the ballast is bolted to the reflector and the channel screws onto the reflector? Unless I'm misunderstanding what you said. Hmm an eight-lamp fixture is screaming for one lamp of each color.
Soft White, /WW, /W, 4100K, 5000K, 6500K, Chroma 75, and Chroma 80.