Happy Friday everyone! Is there a permission that we could set on a Role so that users in that role couldn't change a Contact's Customer/Company association - but still able to edit other things on the contact?

Probably not a permission for this specific field but you could use a workflow to disable the field for certain users or roles Use the set field display type action on before load https://www.mavencloud.tech/blogs/post/set-field-display-type-label-and-mandatory-actions

@MGBC - thanks for the tip!