[AJD] Early A Radiator Knob Question

[scotd1 at bellsouth.net]

I am working on a 1934 A and it currently has one of the large knobs ,#A1198R, on the radiator cap which is what is listed in the PC674 parts catalog dated Feb., 1960. The 42-R Repair Catalog dated August 1934 shows a # AA302 knob and stud. It is hard to tell about the size by the pic but it appears to be the small knob. The only small repro knob I can find is the #D636R from K&K which they say is for the Model D. Is this the one I need? 
Don