no need to reinvent the wheel here. your problem is the same as many others, the fix and the problem are well documented here on the forum.
1) remove all rotted core
2) isolate new core from water intrusion (epoxy + overbore & edgeseal methods)
3) rebed deck plates annually
congrats on the new boat. a survey would have been a good way to avoid the surprise. its not a huge problem but its a critical piece. where else do you have water? you might want to reschedule your survey a couple weeks, have your boat hauled, give it a chance to live in jackstands for a little while to give accurate meter readings, have the whole hull & deck moisture metered. talk it over w/ a few surveyors.
