Hey Mike, the front of the fin originally had a carbon hatch pin installed. Remove the hatch pin and install a 4-40 bolt that goes into the rudder base with a piece of 1/4 ply under the base with a blind nut. No issue at that point. Another thing to think about is if you have one of the original carbon rods for the fin instead of the steal rod that has been in use for the last 6 years. If you plan on doing much knife edge flight, I would recommend changing the rod out.