1934 Pickup Radiator Cap Question

[Ratspit]

I am in the process of building a 34 pickup which started life as a 34 BB heavy. When I first got the truck, the frontend was completely disassembled and in boxes. I was working on the grill yesterday and fitted the trim and emblem on the grill but when I set the radiator cap on top of the grill it just seemed like it might not be the right one. The cap has a slight difference in the edge detail and it almost seems like there should be another piece under the cap.

Any insight or pictures of a 34 radiator cap and trim would be greatly appreciated.