I have been wanting to do the same thing. I ended up just making one out of wood but mine was to hold up fat sacs, not bikinis.
Here is a good thread on the MC site, good luck and please post picks and dimensions if you end up doing it. (I would also build in some cup holders if you are going to cover up the other ones in the bow)
http://www.mastercraft.com/teamtalk/...t=43090&page=4
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