Pearsons of that era are notorious for wet decks, due to the use of gaskets on deck hardware instead of bedding sealant or tape.
The gaskets disintegrated in short order, exposing the internal deck wood to sea and rain water, and rot.
It's a sore spot on what is otherwise a fleet of very good boats. Many a Pearson has had the decks ripped out and repaired.
Check if the decks are sound, and that the hardware has been properly bedded.