Actually, these two cars are Jun 9, 1964 planned build date cars. I also have a third Jun 9 1964 planned build car that has a 6 19 3 date stamp on the left front fender, with the raised triangles.
Also have a July 14, 1964 planned build SJ car with a raised triangle left fender dated 6 17 3.
BTW, when I said "different location", I was referring to the geographic location of the stamping plant (Cleveland) on the no triangle "C" marked fender.
-Scott