I scanned the back of the last 1980 topps card that was missing this morning. The '02 Bonds I have is already in, so I'll dig out my '99 set tomorrow and see if I have either of those.
In case anyone was wondering, to finish the other incomplete Topps base sets :
2007 - Need 7 cards (1 regular base card back, and 6 front/back variation cards)
2009 - If we're counting SP's as base cards, the we need the backs of 26 SP cards.
2010 - 28 SP backs, 10 variation (mostly backs, some fronts), and 1 regular base card back
And yes, I really had nothing else better to do tonight. lol!