I read every how-to article and post about the subject. Figured I'd add my 2 cents should anyone find this thread in the future. I have a short shifter but don't think it matters.
1 - no need to take apart the knob. I did and I can't imagine it helping.
2 - once you unlock the boot from the shaft by turning 90 degrees as illustrated by others pull and pull and pull. I needed three rounds of pulling to force it off.
3 - putting the new one on goes the exact opposite however make sure you seat the new knob/boot all the way down. I didn't at first.
4 - if you don't see the known/boot completely down the gear shift lever it will be impossible to rotate it back 90 degrees to lock. If you only rotate say 70 degree your are basically allowing the boot to separate from the knob.
5 - if you do separate boot from knob it's not the end of the world, just put it back on the only way it can possibly go on.
6 - you should either hear a slight click or feel the knob/boot sets full. Once that happens you can rotate the boot.
Worked up a sweat doing this in 85 degree weather. Sheesh.