I faced a very similar problem when trying to figure out how to do the same thing to a Hobie 16 mast with comptip. I ended up using the foward tang off a Hobie 16 boom which is not used for anything. This has 6 rivet holes and as a result spreads the loads very well. It takes a little bending to get it to fit around the comptip but it is relatively easy to do. This has held up all season