Yes, there is a mast track with 2 or 3 brass nuts buried under the EVA of your deck.
I checked with Tiesda You (the designer @ Starboard) and he says they put in a
mast track just like on a sailboard, then put in some brass T-Nuts ( 2 or 3) with EVA
plugs seperating the T-Nuts.
So, if you carefully trim the EVA to the width of the track, and extra carefully trim the
access (for the nuts) at the back of the track, you will have a normal sailboard style
Sorry if my previous message (which someone seems to have deleted) was confusing.
This info came direct from Tiesda this evening.!
Hope this helps,