In the racing product from about the same time, the oversized cards were, I believe, box toppers. One of the two sizes was a Wal-Mart exclusive. I haven't finished researching those yet, so unfortunately I don't have any more definite answers for you, but maybe this info will give you some clues for finding more facts.
-Tom
Ted Musgrave card collection 98.9% Complete: Cards Known: 1013, Cards Owned: 1002
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