I don't understand the misconception that cards with printing flaws can't be cataloged here. They don't get a *separate* entry in the database like a variation or parallel card, but they can be tracked just like cards with TTM autos or condition problems.
From the list above, the Scott McGregor card is this card:
https://www.tcdb.com/ViewCard.cfm/sid/98/cid/33360/1984-Topps-260-Scott-McGregor?PageIndex=1
The printing flaw (blank back) just needs to be noted in the comments of your entry's details.
Ted Musgrave card collection 98.9% Complete: Cards Known: 1013, Cards Owned: 1002
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