No, he can't. SB60 was passed by the legislature, signed by the governor and will go into effect on 1/1/04. Unless I've missed one, there are only three possible ways to stop it: 1) legislative repeal, 2) court ruling (state or possibly federal) or 3) a referendum.
Executive orders can't be used to repeal laws once they've been signed. That's what a veto is for and it's subject to an override.