I'm not absolutely sure about this, but on the basis of "know your puzzler", I can't help feeling that there's no coincidence that the Mohawk chief in Otto's clue was Thomas Davis, the dead comedy writer was Tom Davis, and the LA Dodgers outfielder Tommy Davis.
I'm not a betting man, but I'd wager that the builder's given name will also be a variant of Thomas.
I can't find the puzzle photo, but there's a likely looking Oldsmobile-engined car built by Tom Davis before WW2, used as a street rod, and also for racing at the dry lakes in the Mojave Desert in southern California.
The caption with the first photo says "The chassis was built by Herb Farrington using two side rails from a Miller Indy car. From there it was basically a shortened '29 Ford body with a long hood to cover the straight eight engine. The grille was made from standard grille work bought from Andrew's Hardware in Los Angeles. The Olds engine had a milled head, Winfield camshaft and Pierce-Arrow ignition. The car was never a contender for top speed, but it nevertheless offered a bit of variety; at the August 24, 1941 SCTA (Southern California Timing Association) meet at Muroc, the Olds was one of five non-Ford entries out of a total of 161".