Somebody out there MUST know what these markings mean.

Dana67Dart said
The more I look the more that makes sense.

K2-3
&
K2
3

K = Kelsey manufacturing
2 = plant 2

3 = year 1973 (67 and older did not have external date markings so must be 1973 not 1963)

8 (valve stem hole) 17

8 = August

17 is the 17th

Thanks, Dana. That's the best explanation yet. I appreciate it!