Am looking at (2) 1984 Oday 28"S and (1) 1985 Oday 31. Love the layout and room. Love the finish of the gelcoat. Love the non-slid decks. The cockpit is sweet. Problem. All 3 have cracks in the top of the cabin top. Not the deck, but the cabin roof. All 3. They look like "stress" cracks, but they are in "non-stress" areas. All 3 boats have them in different location than the others, but not under any winches, at the mast, etc. Very random. What am I seeing. Should I be concern?