Bow cap coring rotted - 20 Seafari

[Max_Florida]

I'm not 100% sure what the area I'm referring to is called. Here is a pic:





I was going to patch the existing hole and reinforce with some plywood underneath. Ended up discovering that the whole area is rotted out. In retrospect I probably shouldn't have started cutting from the top that extensively without getting advice first.

I know ideally I would remove the whole cap and fix it that way, but I would rather not if I can help it.

I was thinking of cutting the fiberglass skin off the effected area, removing the bad core, replacing it with new core, and then fiberglassing over the whole thing. Does this sound like the right way to do it? Would 1/4" Starboard be a good choice for a core?