[Mr70]

"K-1-1 with 4/13 AND K-1-2 with 2/24
What is the "4" and the "13" immediately left and right of the valve stem?

K-1-1 stands for Mfr./Plant/Year assembled for the wheel.
Breaksdown as such:
K=Kelsey Hayes Mfr.
1=Ass.Plant,Romulus Mi.
1 & 2=last digit of the year,1971 & 1972 respectively.

The 4/13 & 2/24 & CZ are the final assemby date & designated application for the ENTIRE wheel as a whole.
Breaksdown as such:
4=Month,April..or 2=February.
13=Day in April...or 24th February.
CZ=used on 1971-2 Chevelle Coupe & Convert. & St.Wagon models,produced by both KHayes & Norris Industries with a .88 offset.