OK, it appears that I have been thrown off by what was on my car at the time I bought it.
Diagram 6D-7 in the '67 Service Manual shows how it's supposed to work. Flat, screw-on non-vented oil cap on 1 valve cover and a grommet with a tube to the air cleaner on the other.
Since my original air cleaner was gone, so was the tube from the valve cover and in it's place was the painted oil breather/cap. I still have the flat screw on cap also.
So it looks like you did not get the chrome oil cap.
2012 Mustang Boss 302 #1918, Competition Orange. FGF replacement 2006 Mustang V6 Pony, Vista Blue. Factory ordered. 2019 BMW X3 (Titled to the wife, but I'm always driving it for her. So I'm claiming it) Old projects, gone but not forgotten: 1967 FB 400, original CA car. After 22 years of work, trashed by the guy who was supposed to paint it. I had to sell it. 1980 Turbo Trans Am 1970 Mustang fastback, 351C 4Bbl, auto 1988 Mustang GT, 5 speed 1983 F-150 4x4, built 302 1994 Chevy K2500 HD 4x4, 454 TBI