Rob, I usually check the tire pressure, clean the rims and tires up real good and stack them on top of each other with a large lawn type garbage bag covering them up if they are to be stored in a dry place.
If you have chrome wheels, you also can wax them and then leave the wax on them for a protective coating.
If they are going to be stored in a damp place, such as a basement, lightly coat them with vegetable oil.
JMHO
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1969 Falcon 1992 Artic White Firebird 1997 Black Firebird 1997 Black Firebird w/Y87 Package