Two suggestion.
1) Glass leash loop (very pretty if done well). From Mellor at Swaylocks
One way is to scuff the area on the deck where you want the loop - I would say approx. 6" X 3" with the long dimension along the stringer. I mask off around the scuffed area. Wrap some wax paper around a pencil and place it across the stringer in the middle of the scuffed area - tape the ends down to the deck. Build up fin rope and sanding resin over the pencil. I also put little cloth patches on either side of the pencil to help anchor the fin rope but I'm not sure if this is necessary. After it cures, take the pencil out, feather the edges and clean up the hole where the pencil was - you don't want sharp edges where your nylon loop attaches thru the hole. Re-mask, gloss and wet/dry sand it - should be good to go.
2) Through the deck loop. Drill a hole through the board, stick a rod+wax paper in hole, fill with lam resin, remove rod when partially set, touch off top and bottom, grind down when done.
I'd use option 1, although 2 is easier. If you screw up 1), the board is still 100% fine, and you can always do it again.