I trimmed the length ot fthe elevator tips to match the counter weight. I then match drilled the holes to the elevator. I decided to back up the fiberglass with a piece of the 1/2" wide .020" aluminum. I cut a piece to length so that I could fold it over to fit inside the tip. I then drilled through the aluminum using the tip holes as a guide. I epoxied the aluminum to the inside of the tip. I then countersunk the holes to match the dimples made in the elevator. Finally, I used the CS-4 blind rivets to attach the tip to the elevator.
I haven't decided exactly what I'm going to do about finishing up the joint. After consulting with some of the other guys in the builder's group, my thought is to use filler to get the surfaces even and then to use a dremel tool to make a small divet where the joint line is. I've decided against using fiberglass over the joint as others have done because of the potential to crack in the future. I figured if there is enough stress to crack at the joint, make it look the the crack was intentional.
