The September/October 2001 issue of Antique Power magazine (www.antiquepower.com) features two articles about the 101; one specifically about Ron Koogler's tractor, and another about the history of the 101 and the man who designed it.  The following excerpts are reprinted with the generous permission of Antique Power magazine.  Visit their web site to order back issues of their magazine, including the September/October 2001 issue featuring these articles.

Only One (or Two) of a Kind by Peggy Shank

His father bought a farm when Koogler was in high school and the young Ron didn't like to be taken out of school to help with farm work.  He didn't like the John Deere B used on the farm in the early '50s either.  In fact, he "couldn't stand it...wanted to get away from tractors."
     But Koogler, the man, has a different view of tractors.  He has a stable full of Deeres, some of them rare, a few implements, and a couple dozen child-size pedal tractors.
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The rarest tractor in the collection, though, is the John Deere No. 101.  Five were built in the early 1940s.  They were loaned out to farmers who tested the tractors for a month and suggested improvements.  When a driver said the regular seat did not give enough back support, for example, a 3-inch strip was welded around the back.  Originally the tractor was maneuvered with a steering wheel, but because it obstructed the view, it was replaced with handles.
     EX, for experimental, is stamped onto the pump, transmission, and rear end.  Other parts came from the Model L, said Koogler.  This tractor in its restored state has most of its original parts except for the experimental hydraulic pump.  It leaked badly and parts for it were impossible to find, so it was removed.  The rear end and transmission work fine, he said.

Innovation at John Deere by Patrick Ertel

All John Deere production tractors were built around one of two design themes - the vertical-cylinder Dubuque tractors and the larger Waterloo tractors with horizontal cylinders.  But that was just production.
     The company was committed to 2-cylinder engines but constantly tested the limits of all other areas of tractor design.  Unconventional tractors were common in John Deere's engineering offices.  One of the company's more creative engineers, Theo Brown, recognized that the general-purpose tractors intended for cultivating single rows - the John Deere L, Farmall A, and Allis-Chalmers B - had a common fault.  The power plant of the tractors was between the operator and the row to be cultivated.  Brown surmised this caused the operator to work in uncomfortable positions in order to see what he was doing, so Brown set about designing a tractor with better visibility.  In 1941, he introduced a new concept at John Deere - the Full Vision tractor.  The goal of his Full Vision tractor was to provide the operator with an unobstructed view of the ground both directly in front and directly to the rear.
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The first running, experimental tractor was built up out of an old model Y tractor.  The engine was moved as far to the rear as possible, the radiator was moved to a position behind the engine, and the operator's seat was mounted over the engine.  The steering post was relocated in a forward location.  This tractor was first demonstrated in the Experimental Department on January 5, 1942.
     In April 1942, the tractor was taken to the Experimental Farm where it was tried out in the field, both with an integral 14-inch plow and an integral cultivator.  Starting June 8, 1942, this tractor and cultivator were used to cultivate corn at the Experimental Farm and later ata private farm, where the crop was cultivated three times, an equivalent of 125 acres.