I've noticed that on my bow seating, port side, the seat back seems to be pulling away from the frame, I have exposed staples I can see when I look straight down on it. I am trying to figure out how that piece comes off...is it the 'Christmas Tree' style clips like used in automotive, but larger? I've felt around in the mid cabin on the upholstery in it and cannot feel any sort of bolt/screw/fastener underneath it that would allow it to come off that way.
Any ideas?

Bolted from the back or the piece on the right needs to come out first.

From my experience on the few pieces I have removed on a couple boats, you need really LONG Arms and fingers!

How about removing the port side glovebox or radio to gain to the area behind the seat. My experience with Baja interiors is that they’re bolted in from behind with 5/16” bolts into speednuts pressed into the wood seat backer.

There's a small mid-cabin that gets me access right behind the seat, and I have tried in vain to find anything that bolts to the seat back. It IS very thickly padded upholstery in there but still, you'd think I could feel something underneath it? And I don't. The left side of that top piece that sweeps around towards the front of the boat definitely has the 'Christmas tree' type of fastener as I can see it; it's actually a bit loose and I can pull the seat back away from the hull some. But I don't see anything similar on the back of the seat that faces forward.

It may be worth a call to XT-Innovations in Ohio. They were involved in the design and manufacturing of the Baja interiors from that generation. I had called them years back when I had my old 260 and they were very helpful and knowledgeable. They even still had most of the factory patterns for the seats back them, I’m sure they still do. They’d be familiar with how those bolsters attach to the deck.

^Sounds like a Plan! Thanks.

Sure thing, good luck. Let us know what you come up with.