How to remove pulley from an S-Trim?

I'd like to change the pulley on my S-Trim while its still in the car. Last time I tried just for curiosity, and after taking the bolt out it clearly wasn't just sliding off, so I let it go. But now I have belt slip and would like to try my Reichard Ultra-Grip pulley to see if its worth any improvement.

From the people I've asked I've heard everything from "heat it with a propane torch for 10 minutes" to "pry it off with two screwdrivers". Both scare me...

What's the hot ticket to removing and replacing a pulley on these units?

Many thanks! Before you ask me how the Ultra-Grip pulley works, please help me install it :D

Last time I changed a pulley, I just removed the blower from the car. It should be 6 bolts, an oil feed and return line, and the intake tubes. Anyway, a standard gear puller was all I used. :)