Removing V Birth Backrest/Shelves That Wrap Around Forward Cabin... How To/ How Secured?

[Repeteg]

Trying to figure out how the v birth backrest/shelf is secured to the hull for removal for reupolstering 1989 280 Sundancer.
There are 2 parts to this question...
A-How is the virtical portion secured to the horizonal shelf/ledge?
B-How is the horizontal portion secure to the hull ? Is it removeable or glassed into the hull?

I don't want to destroy anything by doing this but the fabric covering is shot and needs to be replaced.
I'm very capable just cand find any screws or button caps. Scratching my head.
Any instructions, advise or photos would be greatly apreciated, Thanks!

 

[Lazy Daze]

If you could add some photos, that would be helpful. I've pulled apart quite a few over the years, but posting pics would help to show what exactly you have there.