Very likely these are Santa Fe livestock cars from their earlier classes, possibly Classes Sk-K, -L-, N or -P. Such cars appear on Page 71 of the book, Stock Cars of the Santa Fe Railway and a roof drawings appear on Pages 76 and 80.

A wreck photo showing the roof details of ATSF 56161 (Class Sk-K), a single deck car built in 1907:

http://www.steamerafreightcars.com/gallery/wreck/atsf56161main.html

Bob Chaparro

Hemet, CA