['ol Pinion head]

Mikes HO, the pertinent question is when & what plant was your '71 TransAm built?

the very earliest '71 15x7 Rally II equipped Birds will typically have a set of the very last bult dated JW's

KN's were produced in late July of '70. In the early 90's, one of the KN's I culled up had a very early August date. I've never had another, or seen pics of another dated in August, yet I know
I owned one.

The Fall UAW GM wide Strike began middle of Sept 1970 & ran into mid to late Nov of 1970. Nearly every GM supplier idled their production lines as well during this time.

MotorWheel, the supplier of the JW-KN-KR coded Rally II wheels brought production back on line in early November of '70. KR 15x7 & the KU 14x6 Rally II wheels began to be produced at this time. The earliest examples of either code are extremely hard to find.

When the Fall '70 UAW strike was resolved, the Van Nuys F-body plant resumed production. The Norwood OH F-body plant, as well as the Lakewood (Atlanta) A-body plant both did not resume production until up in Jan of 1971. This created quite wide date spans, ESP on what amounts to low volume installed components.

In the time span of late Nov of '70 to early March of '71, the effects of wheel stock on hand in the assembly plants when they fired back up, as well as the wheel stock waiting to be shipped (in Nov of '70) contributes to what some would consider to not be the "correct" date range of parts. Thats why it takes absorbing the experience of serious longterm collectors & restorers what parts were actually used on the cars.