Mack may not want to take credit for this bus, but that is where the Mack Bros. started in the early 1900s. Regrettably I can give no firm information on this product.
It has Mack emblems , but the Kenworth grille (with a Mack sticker on it) is really a spare tire bracket. The engine is aft of amidships, if those side grilles are any indication. The sheet metal "caboose" on the rear hints at some prior use, but I can't begin to imagine what that was.
Picture taken at my favourite intersection, Queen and Morris, in Halifax, NS, early June 2001.