Hold on a sec, i've had the same problem getting the gear knob off. Here's a better method...
Granted the car looks better with a lower stick, but if you want to refrain from slicing your car to peices, then try this.
1. Remove the gaiter and gear surround, simply by pulling underneath the lip at the bottom, don't worry it won't snap...
2. Next, pull off that little rubber ring that holds the gaiter to the shaft, it just unclips at the front, trust me...
3. Take a hammer, and gently swipe at the knob underneath it, it will loosen up, and you can just pull it off, again, don't worry, nothing will snap away.
Give it a go.
Dan