do thye make .060 over 4.8 piston?
If you're set on the factory piston, a 2007+ 5.3 replacement piston will be the same style - flat top. But if you go that route (if available) make sure to verify its a flat top before buying.
Either way, if he's looking for cubes, or cleaning up something bad, the ls1 bore is the best option IMO.



