Jim K sent me an airbox for my S3 and it looks great. Thanks for the part!

One thing I did notice is the air cleaner top is stamped as above. It has the same numbers as the stock exhaust does for my bike and assuming the 74 has the same thing. The original top for mine doesn't have this stamp. Anyone know if this is pertinent only to a 74? My bike is a 75 and doesn't have this stamp. All the asthetics are identical except for this. May RB or someone has seen this before?

Information may be helpful to the purists.
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