Thanks for the reply. I thought of the mechanical approach but figured... what the hell, I haven't itched from grinding fiberglass in awhile, so I went that route...
I've documented the process, more for years down the road, to remind myself, " don't do this again ! ".
Here is where I am as of today:
Bad core
Removed Bad Core and Potter Putty seam
Aligned Seam before Epoxy
Epoxied Seam
Glassed in new core
NEXT... DuraGlass the core seams. Glass over the core and then use several layers of 1708 over the epoxied seams.
I'll send more pix.
I figured basic structural repair and then, because the main repair is hidden, I'll build it extra beefy... The repair area I need to learn a lot more about is color matching gelcoat - THAT IS TOUGH !