Transferring Supervision of a Retired Minister?

I am a clerk of council and need to transfer the credentials of a minister who has since retired and joined another congregation. Article 18 of the 2016 Church Order states that "This transfer is to be made in the following manner: the council of the church which the emeritus minister served last formally requests the council of the church which the emeritus minister wishes to join, to exercise supervision over the minister." Is this an actual form (like the Ecclesiastical Credential for Minister), or can I simply draft a letter requesting the new church take over supervision?