Dizzy rotor is stuck on?

[SmogSUX]

I bought a dohc S13 motor and was replacing all the tune up items. When I got the the cap and rotor I went to pull the rotor off but it wouldn't budge. It spins with the motor and all like it should, but it just doesn't want to come off. I ended up prying it off with a screwdriver, but broke it. No big since I was putting a new rotor on right? Nope...it's too damn snug to put on.

So I bought a used dizzy with cap and rotor, but this rotor is stuck too....I don't get it. I've never had a car's rotor be like this before..

Any idea what's up?