Originally Posted by Igneous Faction
Rather than use hammers, mallets, etc... use the home-made DIY headset press. A LONG bolt, a nut, and a stack of really wide washers!
This method worked well for me, until I managed to crack my miche HS in half. Still, I would much rather use a makeshift press than risk ovalizing the headtube with the mallet/woodblock approach.