Hchris,
Here are the Serial Number ranges from my 1926 National Used Car Market Report Red Book, starting from 1920.
1920 266801 to 329680
1921 329681 to 337100
1922 337101 to 388529
1923 388530 to 444231
1924 444232 to 492824
1925 492825 to finis
Red Books were put out at the time the cars were still new (and used) and are trustworthy;
the numbers are very close to yours. Hope this helps somewhat.
TG
_________________________
Luck is when Preparation meets Opportunity.