Racing history from old movie

I am watching "The Awful Truth" (1937). I have freeze framed a very short clip where Cary Grant is in a boat race. The race appears to be staged for the movie in Long Beach CA, on a day with small roller waves. Racing numbers on the inboard runabout are: U/W 11. This rig has the engine mounted behind the driver and racing mechanic. The other boats in the film have front mounted engines as I am accustomed to seeing for all inboards from the 30s. It is interesting to know that inboard racing runabout had the current engine placement as early as the 30s.

Also of note is that the racing "helmets" are cloth and goggles.

I had a second thought: the rear engine boat I saw in the Cary Grant movie could have also been a hydro and not a runabout. I just remembered that in those days, hydros were single step, did not have rounded bows and were shaped like runabouts, so its hard to tell from the film shots.

Did a little research and found a late 30s rear engine limited hydro. See "F=1" on the attached photo.

Came across this in my search for old rear engine inboard rigs.
"Another interesting historical air boat is this sleek retro looking French built Farnam "Hydro Glisseur" circa 1924. This vessel isn't quite sure exactly what is. Part air boat, part car, part airplane, and part hydroplane. It was capable of about 60 miles per hour."