A full history of the Willis/Harrison organ will appear on this page shortly.
| Pedal | Great | ||
| Double Open Wood | 32 | Double Diapason | 16 |
| Open Wood | 16 | Open Diapason no. 1 | 8 |
| Open Diapason | 16 | Open Diapason no. 2 | 8 |
| Bourdon | 16 | Flûte harmonique | 8 |
| Dulciana | 16 | Gamba | 8 |
| Octave | 8 | Principal | 4 |
| Violoncello | 8 | Flûte harmonique | 4 |
| Bass Flute | 8 | Twelfth | 2 2/3 |
| Super Octave | 4 | Fifteenth | 2 |
| Open Flute | 4 | Mixture (12.15.19.22) | IV |
| Mixture (22.26.29) | III | Mixture (17.19.22) | III |
| Contra Trombone | 32 | Double Trumpet | 16 |
| Trombone | 16 | Trumpet | 8 |
| Trumpet (Great) | 16 | Clarion | 4 |
| Clarion | 8 | Swell to Great | |
| Shawm | 4 | Choir to Great | |
| Swell to Pedal | Solo to Great | ||
| Choir to Pedal | |||
| Great to Pedal | Swell (enclosed) | ||
| Solo to Pedal | Lieblich Bourdon | 16 | |
| Geigen | 8 | ||
| Choir (enclosed) | Lieblich Gedackt | 8 | |
| Contra Viola | 16 | Salicional | 8 |
| Principal | 8 | Vox angelica | 8 |
| Claribel Flute | 8 | Octave Geigen | 4 |
| Viola | 8 | Lieblich Flute | 4 |
| Celeste | 8 | Flageolet | 2 |
| Octave | 4 | Mixture (22.26.29) | III |
| Flute | 4 | Contra Hautboy | 16 |
| Piccolo | 2 | Hautboy | 8 |
| Quint | 1 1/3 | Cornopean | 8 |
| Mixture (15.19.22) | III | Clarion | 4 |
| Cor Anglais | 16 | Tremulant | |
| Corno di Bassetto | 8 | Swell Octave | |
| Trompette | 8 | Swell Sub-octave | |
| Tremulant | Swell Unison off | ||
| Tuba (Solo) | 8 | Solo to Swell | |
| Choir Octave | |||
| Choir Sub-octave | Solo | ||
| Choir Unison off | Open Diapason | 8 | |
| Solo to Choir | Stopped Diapason | 8 | |
| Swell to Choir | Principal | 4 | |
| Spitzflute | 4 | ||
| Nazard | 2 2/3 | ||
| Fifteenth | 2 | ||
| Open Flute | 2 | ||
| Tierce | 1 3/5 | ||
| Larigot | 1 1/3 | ||
| Mixture (15.19.22.26) | IV | ||
| Cromorne | 8 | ||
| Tremulant | |||
| Tuba | 8 | ||
| Solo/Choir manual exchange |