I decided the other day to try to remove my fins and see if I could maybe get a larger fin for the center and plugs for the sides so I can do a single-fin set-up when it's small and mushy, and go back to 3 when it gets a little more real...I removed the screws and the fins wouldn't budge. I don't know if maybe they've been in there awhile and will move with some coaxing, or if they were somehow permanently attached even though they appear to be removable b/c of the presence of screws....this is the only board I've ever owned so I don't really have any experience with this sort of thing. I have a not-so-great pic of the fins so you can tell which removable system I have (if they are even removable at all). Having never fooled with one before, I have no idea what it may be.
The side fins have a small hex screw set into the board at an angle at the front of them and the glass goes right up to where the plastic base of the fin starts. The center fin has a normal screw going through its base, but that screw only goes into a small metal bracket that sits below the fin base. It is not attached to the board in any way other than appearing to be jammed into the fin box.
PS: it's possible that I shouldn't even mess with the set-up anyway since it's worked for me in the past, I just got the idea that maybe I could make the board a little more stable in the smaller summertime surf we get around here if I converted it to a single fin.