Auto patrol serial

Hello
WHAT IS THE AUTO PATROL SERIES NUMBER OF THE POSTED PHOTO?[attachment=57245]aUTO PATROL.jpg[/attachment]

8A , the first few hundred were painted gray and known as auto patrol and after that they changed to the no .9 and were yellow. Had the same engine as the big 20.

I thought they changed the colors in 1931 and that was when the auto patrol was released which the the only model was a no9 then in 1936 the no7, no10 gas or diesel, no9, no11 diesel or gas. This is what I have read
That one looks like no9 it looks early because of the front wheel hubs.