Throughout the summer and early autumn, the CTA has been running a 75th Anniversary 4-car set of 5000-Series L cars in the livery of the old 6000-Series cars, in Colorado Spruce Green, Croydon Cream, and Swamp Holly Orange. 6000-Series cars ran on the CTA from the late-1950s thru the ealy-1990s.
img src - trains.com
src - youtube.com user "Chicagoland Transit"