The Rock Island Plows sign.

One of the strongest surviving physical links to W. J. Whiteman's Goodwater mercantile life is an original metal advertising sign.

The sign bears the wording “W. J. WHITEMAN / GOODWATER, OKLA.” above Rock Island Plows advertising.

Roy reports that the sign originally hung in the Whiteman Mercantile store and later came into his possession. The exact manufacturing date is not claimed because it has not yet been established.