Fixing the transom.
I found a youtube channel, boatworkstoday. This channel has been a huge help for me, highly recommend. This channel not only shows how to do certain tasks, but helped me in selection of materials. I'm out east, and without much for local sources I have been ordering just about everything for fiberglass through jamestown distributors. 1708 and 1700 glass, totalboat epoxy resin, fairing compound, silica and chop. The coosa board is from a place in FL and supplies like chip brushes, fin rollers, gloves and stir sticks (tongue depressors) are from amazon. I opted for epoxy because I didn't know all history of the boat and since it was already painted, I felt epoxy would be the strongest method to use.
After all of the transom wood was removed, I bolted a piece of plywood to the outside of the boat and started removing the inside layers of fiberglass that had delaminated. The plywood had packaging tape on the face to reduce chance of it getting stuck to the hull. I had sections of hull that were about an 1/8" thick here and very weak, so that plywood was important.
After removing the delaminated sections, I ground the edges to as best of an angle as I could and started tracing for the 1708. I glassed in the 1708 with epoxy resin, and got everything within 1/16" of flat. I then used epoxy fairing compound to get everything completely flat.
Next up I made a template, then cut out the coosa board. The coosa was fitted, rounded the edges, then sanded and prepped to go in. I mixed up some thickened epoxy and set the coosa, clamping it down. After that had cured thickened epoxy was used to give a filet around all edges.
A final sand, then 3 layers of 1700 went over the coosa. I trimmed the edges around the hole for the jet drive, and will later seal this up with epoxy.