14x6 Wheel Information Confirmation

[Desert 70 Cuda]

Hello,

I'd appreciate if someone can check my work. Recently purchased a 14x6 wheel and based on the stampings I've concluded it's a May 15th, 1975 wheel with part# 3580060.

The part number 3580060, based on what I've found is a 1972-74 for "B" body wheel. It was manufactured in 1975, correct? Or is the year range the lifespan of the part number only? Or is the year range of the part number when it was manufactured and the date stamped right before it was installed on the vehicle? I'm confused by the "M35_5_15", the 5 after the M3 is supposed to represent the year which is outside of the year range of the part number.

Thanks, just looking to better understand.

 

[pschlosser]

Your data looks accurate, to me.

A physical part and its specific part number (for any part, not just wheels) may have been shipped from the factory on only certain models, and certain years. But these parts were available from the parts counter at the dealership, too, even years after the model year of the car.

if your M35 indeed refers to 1975, then is seems possible this very wheel was not shipped on a 1972-74 B-body from the factory, but instead ordered through the parts counter a year or so later.

Another example, the date codes on Carter carburetors can be newer than the cars they came on, because owners could still order new parts years after the given model year ended.