P.T.Rathbone of Marsing Idaho USA has printed 2 large books on wrench collecting. The History of Farm Implement Companies and the Wrenchs they issued Volume 1 and 2. They both have a lot of Massey, Wiard Plow, Johnston Harvestor, Wallis and JI Case plow wrenches. The web site is www.rluckystarranch.com
. This may be of some help to you.