Quick Update . . .
I had a follow-up call with the Naval Architect yesterday. He is going to run a speed/power analysis on the new hull configuration, given that there will be 42" of additional planing surface.
We've had some discussion on the transom, as he indicated the need for a solid core in the areas of the engine mounts (G10 material, which is epoxy-based). I had some concerns about epoxy vs. VE as well as the need for a solid core vs. the Coosa as the core.
After discussion, the light bulb went on . . .

. . . The combination of the clamping force of the engine bracket and usage over time will tend to depress the core, if it were a 'softer' material, and weaken the overall lamination. It's a longevity thing. (OK, I get it

) . . . the Coosa is much 'softer' than the fiberglass.
G10 is wicked pricey, ($650-ish for what I would need) and not entirely friendly with the VE resin, but the N.A. suggested that I could make the core if need be.
So here is the plan . . .
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I'll cut out the 2 'engine mount' areas in the Coosa board and 'fill' the voids with fiberglass . . . probably will use some vacuum-assist to get a good density of glass. Then the entire transom will get more glass to build it up to a desired thickness. . . and even more glass for installation.
Works in theory . . .
