Sorry we got off the path a little - all this boils down to:
1) My original '69 Z stick is the flattened handle GM6041-M-Quality MS Oil marked, no other part number.
2) My '74 parts manual calls for the 3951576 stick, as does the pan instructions for the 3974251 NOS pan. This pan appears to be the intermediate number (or consolidated number) issued in '69 or later to encompass all three years. That number changed again in later years to (If I remember correctly) 465220, which was black EPDM or painted, but visually correct with the provisions for the factory 302 windage tray. I would take a picture of the one on my '68 Z, but it is assembled on the stand -
3) I'll shut up now 'lest I rile everybody. Just trying to help -