Here is what #9 really looked like in the late 30's. March 12, 1939, to be exact, and note , if you will, the new cast numberplate we discussed yesterday, and the red interior of the tender bunker.
The numbers and lettering scheme are exactly consistant with all Standard Gauge engines on the C&S at that time. If the "Q" had so ordered, all C&S narrow gauge power would have been lettered in this fashion, same as #537. Instead, the lettering system used on the C&S Narrow Gauge fleet remained the same as the C&S used on all locomotives prior to acquitision by the "Q" in the 20's.
Interestingly, the actual date of the picture in William's link is 4/9/37, at the end of mainline operations. No evidence whatsoever of polished numerals on the cab sides. Not in that picture or any others taken at that time.