8 3/4 Center Section

[SuperSam]

I have a 8 3/4 rear center section casting # 1634985. It accepts a 1 3/4" pinion bearing and has the letter "N" on the left side. I'm thinking "N" for nodular iron. Can anyone confirm this?

 

[68GTX4SPEED]

That's the same as 742 but an older version, I think 1957-63

 

[moparsteve636]

Correct! late 50s to 63 might be 62 though.The 741 case came out in 63 also!