Terry
I had the same problem one year. When wintering ashore I ensure that I rest the boat with at least a 2 inch block of wood under the forward end of the stub keel making the bow higher with a fairly pronounced slope down to the stern. This helps ensure that puddles don't collect on deck and seep through the fittings and joint and also helps the drainage out of the cockpit also.
Whilst sailing I found that water/spray coming over the deck made its way into the hatch garage and trickled down the hatch tracks onto the cockpit seats.
I put masking tape round all the joints in the hatch garage and put sikaflex in all of the grooves (not too deeply). This can always be cut away with a Stanley knife if you need to remove the covers.
The 20mm drain holes either side of the hatch garage were not much good.
Mike Edwards
Seal 28 "Aztec"
Mike Edwards
Seal 28 "Aztec"