Updated though online information from Jayson R. Engquist. -- The ZIMMER instrument (Op. 173 of 1976) is extant. It has one rank (Angelic Trompette) added by Levsen in 1984.
Updated through online information from James R. Stettner. -- The organ is free-standing and encased in the rear gallery with a detached console. The Positif is in Rückpositiv position on the gallery rail. The expressive division is called Choir. Dr. Paul Bunjes was the consultant for the project.