Dan and Jeff,
I have an SP book entitled "Revised Classification and Assignment of Locomotives" dated May 1, 1930. It has hand revisions up through Jan 1938.
There is hand revision indicating that changes were made to #22 at Ogden with a completion date of 3-20-37 (see below).
All of the information on these pages appears to match what was used by Diebert & Strapac in the SP
Steam Locomotive Compendium
Note that in 1930 the 1, 8, 9 18 and 22 were listed with the initials N-C-O. (Probably because of an N-C-O bond issue.)
Brian Norden