Colvin in CBTN shows the 041 was used (I assume in rare cases) as an alternative head on the Z's, and unverified as the Corvette 350/350 heads. I guess it might be possible that they could have been installed on a 350/300 by mistake (same 041 head with 1.94/1.50 valves). Depends on how long you have known the engine - possible upgrade at some point to the 2.02/1.60 valves ?
Aberrations are difficult to explain, even more difficult to verify.
one family vehicle
I understand that they could have used, though not very likely, a 041 head on a 302 or a 350/350 - but from what I know, those types of motors were all built at Flint. I am under the impression that Tonawanda did not build any of the 302 or 350/350 motors, thus would not have had a need to install the larger valves