Thanks for the info. I'll stick with the "If it ain't broke, don't fix it." Just wasn't sure if re-pasting GPUs was a common thing or not. The cards these days aren't like the ones of yester-year where it was just a finned block welded to the card. Was applying my PC maintenance mind-set to the cards.
Cool beans, the kid will be happy. The 2 GTX460's will be a good boost to his box from what he's got now.