Not worth the effort when you could probably pickup a "faulty" G4 iBook for < $20. It seems the longer the issue is left unrepaired, the worse it becomes.

I don't like using a heat gun on PCBs - it rarely works. The heat spread is too widespread, and the BGA (balls of solder) when melted make the component "slippery" and it moves around - put it out by the tiniest degree, and you've stuffed it even more, beyond repair.