I don't like the way that Maxum molded a channel to mount the bow roller into. While it gives a nice clean line on teh deck, they used a lot of 2" bow roller's making it tough to replace. What you're probably looking for is something like this self-launching equivalent:
What I ended up doing was milling a piece of ipae then selaing it, then using it to fill the groove, then used 3m 4000 to seal it and the bolts for the bow roller. The bow roller is wider than the groove, so the groove and sealed ipae are completely covered. I'm strongly considering going back and fiberglassign the whole thing in.