In 1924, the January issue of The Diapason announced the completion of the High School organ and the July edition of The American Organist carried a long article by Richards about the instrument. The 'July' stop list differed from that shown in the contract, but it is not clear if changes were made as construction progressed or after completion of the instrument as originally specified in the contract, or both. It is hard to determine exactly what alterations took place, but it appears that some stops were added or replaced while others were simply renamed, e.g. the "Mixture" on the enclosed Great became "Cornet Mixture".

Although comparison between the Contract and July stop lists may not reveal every change that occurred, the following differences have been noted by the author:

Choir
• Dulciana unit, 12 pipes added (making 97 in total) for a 1-foot extension.

Unenclosed Great

• Bourdon 16' added, duplexed from unenclosed Pedal stop #104.
• Cone Gamba 16' and 8' added, duplexed from unenclosed Pedal stop #109. Both registers were previously on the (enclosed) Solo.
• Grand Diapason 8' and 4' added (73 pipes).
• Flute Overte 8' added (61 pipes).
• Tuba Sonora 8' added (61 pipes, 20" wind). Playable from the Great and Choir. According to some stop lists, it was also available on the Pedal at 16, 8, 4, 2²/3, and 2, in which case 73 pipes would be needed.

Enclosed Great

• Contra Violone 32' and Violoncello 8' added, duplexed from Pedal stop #116 (in Solo box). Both registers were previously on the unenclosed Great.
• Diapason Phonon 8' added (61 pipes).
• Horn Diapason 8' added (61 pipes).
• Seven-rank Grand Cornet (sometimes referred to as Grand Chorus or Grand Mixture) added (73 notes per rank, 511 pipes in total), with independently drawable ranks (1-5-8-10-12-14-15). It has been suggested that these were the mutations provided by Losh, but this doubtful as his interest in the subject was confined to tone-coloring mutations, which created synthetic stops, rather than those that were part of the Principal chorus) .
• Harp extended from 49 notes to 61.

Orchestral

• Two-rank Violin Vibrato separated to provide two registers; one tuned sharp, the other flat.
• Composition of String Mixture revised to 10-12-15, from 15-19-22.
• Both percussion registers (Chimes and Harp) removed.

Floating

• Lieblichflote 16' added (61 pipes), replacing the 16-foot octave of the Gedeckt unit.
• Gedeckt unit revised to provide registers from 8'-2', rather than 16'-2²/3' (requiring 85 pipes, instead of the original 90).
• Gemshorn Celeste rank (49 pipes, to T.C. only) increased to 65 pipes, in order to provide 3¹/5 and 1³/5 registers.

Solo

• Cone Gamba 16' and Muted Gamba 8' (duplexed from unenclosed Pedal stop #109) removed. Both registers were made available on the Great organ instead.
• Viol Celeste 8' added (61 pipes).
• Bombarde unit added (85 pipes). Playable at 16' pitch from the Pedal and at 8' from the Solo, where it was provided with an ocatve of extra pipes.
• Horn 8' (from enclosed Pedal stop #115) removed.

Echo

• Gedeckt unit (85 pipes) replaced by Spitzflote unit. The celeste rank was also replaced by a Spitzflote, although its name, Flute Celeste, was retained.
• Viol Sordine 8' added (61 pipes).

Trombone Chorus

• Each pitch of this compound stop was given its own stop-key, thus providing five separate registers (16-8-5¹/3-4-2²/3).
• First Trombone rank listed as having 92 pipes, instead of 80. Presumably, 12 extra pipes were added.

Fifth manual

• Added as a home for the Antiphonal organ (Trombone Chorus and Echo divisions) which, previously, had been floating department.

According to figures given in the July article, these changes meant that the enlarged instrument possessed 72 voices, 86 ranks, and 5,774 pipes. However, if the various alterations listed above are taken into account, the totals become: 74 voices (plus two percussions, making 76 stops in all) and 89 ranks. The number of pipes was 5,960 - if the Great organ's Tuba Sonora had 73 pipes, not 61.