Shell Support Arms Pocket question

I have found several threads that state how to adjust the shell support arms at the point where they meet the torsion part.

Has anyone ever had to repair where the support arms are bolted into the shells? Since the arms also pivot at the shells, can (I guess the term is called a pocket) this pocket wear or wallow also?

The reason I ask, is my TM is barely engaging both of the the spring-loaded hook latches on the curb side. The hold down pins on the shells barely hook on the very edge of the hook itself. This has caused the point of the hooks to wear off and let my shell become released.

My local TM dealer said that it sounded to him like the pockets inside the shells were wallowed, and needed replacing. I am not doubting, what he said because they are an excellent dealer with first rate customer service.....I am just wanting to learn for myself exactly what these pockets are. I assume they are something that goes inside the shells that holds the support arms, to let them pivot. Anyone with advice or experience with this problem, I would greatly appreciate comments.

Thanks