Use two layouts, one were access is permitted, one where it is not. Use scripts, possibly with script triggers to take users to the correct layout.
Put two copies of this field right on top of each other. Set up one to permit access and one to deny access. Use FMP 13's "hide object when" feature on both copies of the field to control access to this field.
Example expressions you might use.
On the copy that denies access: Get ( accountPrivilegesetname ) = "[Full Access]"
On the copy that allows access: Get ( AccountPrivilegesetname ) ≠ "[Full Access]"
This will hide the noneditable copy from Full Access users and hide the editable copy from users that are not Full Access.