i just checked my original low miles jack assembly on my 70 LS6. my lug wrench also has the "O" stamped on the top and the paint is very thin with semi gloss black.you can almost peel it off with your finger nail as thats how thin the paint is on there.
also my jack assembly and bottom base plate both have "0C" marked on both of them which i guess would be the date code of 1970 March,makes sence as my car was built on the 3rd week of April.
