I suspect its one of the last years built, judging by the engine choice. Worthington sold out to the Jacobsen mower (Racine Wisconsin) company about 1953. (I remember talking to a fellow who went to work for them right after his time in Korea.) Jake carried the line for many, many years under their name. They were primarily built to tow the ground driven reel mowers used on golf courses and other large tracts.
C.C. Worthington is also the same Worthington that had the Worthington Pump and Compressor Co. He also built the Shawnee Inn and Country Club (1907) in eastern PA. I knew two of his grandchildren, two other brothers owned a Jake franchise in Mass (Sawtelle Brothers) Check out Shawnee.com