Here's what I have for my HO Scale Clinton Sub Local. The RPO-Baggage is based on 115, a 1906-built car that was steel-sheathed during 1936. It is very typical of the 15 foot RPO and 4-doored baggage car that served the High Line. The chair car is based on 770, an class of '23 ACF car. The monitor-roofed car was rebuilt and air conditioned (Waukesha) during 1941. The roof ducts were added during that modification.