Here's the passenger seat slid all the way back, as it is most likely to be used. Allows passage past the doghouse and the right armrest clears the door armrest but the seat interferes with easy in- and egress through the side doors. It would need to be slid forward to improve that, and also for swiveling.
Driver's seat fully reclined with the dog's seat spaced back to allow that. Way too much space wasted on a setup unlikely to be used once a bed is in the van.
Here's the third pedestal that is stenciled "Universal" and this one is only tacked down in the van for now. It's secure enough for the dog to ride on but will be bolted in place later when its position is finalized.
This seat position makes more sense for us; the dog can squeeze in and it leaves us more build space behind it.
Our new home! They'll be removed again for upholstery cleaning, pedestal painting and lubing, and so I can rip out the old flooring for the start of the interior work. The driver's seat will likely get washers under the swivel base and under the mounts for the seat rails on top of the swivel base (looking for +1"), and I'll try to mount those rails more rearward, all for more legroom.
The bride is interested in trying out the single-armrest grey buckets in the Coachmen van still in the junkyard. I'm going back for some more interior pieces and some other junk so we can test them, but I suspect that their mounting bolt spacing is similar to the stockers and they won't fit the swivels without too much work. For that much effort I'd want better seats but I wouldn't be as picky about bolt-ins.