Maybe something like the excel. I can see them being pretty handy I think and they dont take away from floor space.

the guy building my new rig is making one whole side (the shooting side) of my boat a shelf (if thats what you mean by trays) with cup holders. I seen a couple other rigs he installed them on and they looked and funtioned well

I have an xpress boat with the T-Rail system and I had trouble finding the cup holders and shelving if im not mistaking the excel boats are same way with T-rail? But I found a website from War Eagle they have T-rail accessories here is link.
http://www.wareagleboats.com/accessorie ... l-products

I ordered two from Avery and had them welded inside my boat

My buddy has trays on the rails of his boat. I think they're made by muddbuddy. They hold a box of shells and a cupholder and are really well made. I'll try to find a link.

Edit: I found what my friend has in his boat. It's made by Excel.

Half-way down the page:

http://www.excelboats.net/Excel%20Store.html

I mean like a full length tray down one or both sides of the boat...kinda like the excels have in them...

I'm sure someone close to you can fab ya one, and make it removable