Looks like the
leaks were coming from the ceiling vent and the inlet to the "city water" connector (which was dry-rotted) Those black dots were just where the foam separated from the vinyl cover. Scrubbed half of the interior with TSP tonight, will try to finish tomorrow. Hard to get in done working full time and juggling a 4- and 6-year-old, but we'll get there. Really want it sleep-able by Memorial Day weekend.