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Autozone isn't your best solution. They offer universal ones that don't work with our set ups. My suggestion is to go to a Napa store or older mom and pop that can get you real stuff. GM dealership may also be able to get them.
Funny. That's the same expression I had the first time I encountered that switch substitution - at a GMC dealer no less - with an OE party number. The two styles of switch should be interchangeable. IIRC, the superseded part adjusts by rotating the body of the switch against an internal detent - there may be a release lever involved ... or a shear pin.