Norm's got it.
 

This is very sound advice. Spend some extra because it is such a small area (and not to mention on the underside of the boat) You'll get a far superior bond out of epoxy. Get yourself some of that 1708 stitchmat too. I did a thru hull in my sailboat that was 2" and feathered back about six inches in all directions. (bout a 12" circle) Start with a small round cut of fiberglass for first layer over hole and get larger diameter-wise each additional layer. I remember the first two layers I did I put one on the inside of the hull and one on the outside to bond together real well initially. Use some wax paper in direct contact wit the hull/ patched area/ a flat piece of wood next, and then a stick or leg to hold the plywood from falling down.

Remember to clean good with acetone/ alcohol and rough it up pretty good.

I am half done. 5 layers of DBM on the inside. With vinylester epoxy. THe outside will be the same. I will use peel ply and a beach ball to "compression mold" it as it is almost updsie down. It looks strong so far and should be fiber rich.

I wish I was running the boat, but I am becoming more happy with the structural improvements. I just want some 24" props. Hoping I can hit just under 50 MPH on race gas (stuff with a fast flame front for high RPM torque where the prop needs it). Heck, if I can pull redline with 24" props, thats a start.

One of these days.