Mast Step
The Pearson 10M has a steel mast step sitting in the bilge that leads to galvanic corrosion problems with the base of the mast. Details can be found on this site:
dan.pfeiffer.net/10m/
Other models with this problem: 323, 36, 365

Mast
The 10M mast is a Sound Spars 8755 (Mast Section: SS-8755MB) tapered at the top (possibly by Pearson). According to RigRite It is the same section as used on the P36 and 424. RigRite sells parts for the mast including a mast boot that fits over the special Pearson cast deck collar.
www.rigrite.com

Chainplate Knees
10M's up to hull 101 or so (1975) had the main chainplates attached to fiberglass knees (partial bulkheads) that were glassed to the hull. The bonding could be weak and tear away or there could be deformation in the hull from the rig tension. Details can be found on this site:
dan.pfeiffer.net/10m/

Keel Fairing
There is a fiberglass fairing on the trailing edge of the keel. This fairing is vulnerable to dammage in a grounding if the boat is twisted to free it. It is also vulnerable if blocking is placed under it when the boat is hauled.
Photo of keel with missing fairing
Drawing showing fairing outline

Cover Frame
Info on building a PVC cover frame