When I bought the boat 3 or 4 years ago it had blown off and gotten run over, but they followed the PO with it and gave it back. I have had it re-done once, using the old one as a template, and I left the boat there at the shop. It looked/worked good because it still had the original hardware. Last year it blew off at some point, which i noticed after getting a flat tire on the trailer .....
This time I took some measurements and modeled the base in ProE and created a print for it, and then made a cardboard cutout from it to verify the fit. I am not making the base myself as I don't really have the right wood working tools to make the curves. What I really would have liked to have done is printed the print full scale on a plotter and used that as a template, but I didn't have time. Hopefully they get it done for Memorial Day.
I haven't decided my long term solution for attaching it, but I got a roll of industrial strength velcro that hopefully works for this weekend.
I can attach a PDF of the print once I get the piece back and verify it fits OK if that helps anyone out.