I'm trying to get a letter from the VA saying my condition for discharge as cleared up. Do I go through MH or my PCP?

Your PCP needs to have a conversation with the MH doc, the two should coordinate and agree on a "Narrative Summary " which briefly outlines your past diagnosis and treatments and current status. Stress this is a required letter for re enlistment to expedite the process. If you want to chat DM me & I'll help guide you. Best Wishes

In order to re-enlist? For rating? You can PM me if you prefer but not all diagnosis "ICD codes" disappear, some can be recoded as "history of" or stabilized. Unless it was an error, I would expect it will remain in some form. Kind of like a scar from a surgery.

Go to a local Veteran Service Representative. They can better guide you and will assit you in the process.