Potting deck hardware, keeping the core dry

[kenfyoozed]

I know how you would normally go about "potting the deck hardware wherein you remove the core material between two laminates, fill will resin and redial the holes. Thus not allowing any water ingress to access the core material. My 26D has no laminate below, or underneath the core material. The core is plywood that seems to be adhered to the deck underside. Most places you are not able to even access the underside other than to remove the nut from the fastener. So how have other dealt with this? Any ideas?