Just wanted to share what we (OK, A really smart retired engineer named Wayne) came up with for mounting towers to a curved surface. We were not able to find anyone who had addressed this problem yet, so here's what we've come up with.
- - Skip this paragraph is techie stuff bores you - -
On a rectangular base the axis of the curve will likely be in the long direction of the base so by opening up space in the center of the base pad (that goes between the boat and the base) it allows it to "straddle" the curvature of the boat. By using a radius on this edge, as the base is tightened it allows the material to "mush" to match the contour. The correct material & durometer of the pad was the hard part. By using a much thinner edge on the ends it allows the pad to contour to the boat curve. An added benefit is it moves the pressure away from the boltholes, lowering the stress on the gelcoat at the holes, which should reduce chances of stress cracks.
See picture below or at http://www.monstertower.com/productspaws.html
Love to get some comments on the idea.