I assume this is all about getting the transom in, so here is what I recommend.
1. Attach transom to hull with thickened resin.
1a. Spread thickened resin across the back of the transom at least 1/2 inch thick, you can avoid the I/O cutout.
1b. Lag or clamp transom in place and leave overnight. You want resin to ooze out all around the edge of the transom. Use a bondo spreader to smooth it all out, and fill any gaps. You want to have a smooth transition from wood edge to hull glass.
2. Next day, use a grinder to scuff up all of that resin. Leave as smooth of a surface as you can.
3. Gather all of your glassing materials. You want two layers of csm and one 1708 across the whole transom, and at least six inches past all the way around. Cut the 1708 just a bit shorter, so it doesn't hang past the cam. Fill any low spots with more csm.
4. Start glassing. I can do a quart cup of resin at a time, but depending on your speed and temp, you might start with half. Do the 2 mat, roll out all of the air bubbles, 1708, roll it.
There's no down time once you start, you're racing the clock trying to get done before the resin sets up.
This might help.
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