Playing in Google found another candidate for manufacturer, Hewitt Motor Company, of 10 E. 31st St. NYC.
Found illustration with similar overall shape and near identical tire treads; in an illustration of a period ad on ebay and on pinterest but I'm not going to link to either of those websites.
Note that search results for Hewitt Motor Company overflow with todays HMC.
What I will link to is search results from the Detroit Public Library, results for Hewitt truck, which won't be exact match for truck which started this, but will show the manufacturer's existence,
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