The shells are designed to be used with the Atlas U30C, U33C or U36C Chassis.
The ATSF (Atchison, Topeka, and Santa Fe) railroad SF30C, is a type of six-axle 3,000hp diesel locomotive rebuilt by the ATSF from GE U36C units they owned.
70 were built, a few still exist and are still in service on various shortlines and industrial companies; but are exceptionally rare in the US. Many are employed by ALL and MRS in South America.
Some of the photos below show a built up kit by Motown Models. Chassis, electronics and beacon are not included in the kit.