If it’s any help, I found that the leak which which was affecting the ply panel behind the starboard shelf in the “V”-berth of my Classic 30 and collecting in the bottoms of the forward lockers was originating at the bolt at the aft end of the pulpit. Over time I have detached and rebedded quite a few of the deck fittings on my boat.
Like Andrew Spruell, I would recommend blue paper towel as an aid in detecting the origin of leaks.
The membership association for owners of Dufour Yachts