Looks like I'm scoring a bunch of 1950s/1960s "Louver" fixtures and F40SP35WM. They're beat up, have been rained/snowed on outside in Interior Alaska for 10+ years, but I think I can make one good one (at least a 4' section, most are 8' but one is 4') out of all the parts and much bending and spraypainting with appliance epoxy.
The one ballast I saw was an old, old GE. Surprised they didn't all cook with 34w lamps, as some still had the lamps installed, though we found a bunch of the same lamps elsewhere on the property full of (mostly) trash. Most are post '95, pre-03, but at least one that isn 't broken is a pre '92 model, and another appears to be a Sylvania SuperSaver Designer 3500k.
Despite being crappy 34w, they're SP35, an anomaly...