Marx produced a fine line of plastic diesel switcher engines from 1955 to 1975. There were two basic sizes produced.The earliest was a grand group of Alco S-3 switchers, they were the top of the line model....
4363 and 4362 Santa Fe Crusader and Cannonball Freight Twins The Great American Railroad series was one of the last produced by Marx. Here are the main dozen sets listed in case some of you Marxers...