Either you can test your manhood and spend 4 hrs manhandling it off after a few beers and tons of swearing while someone laughs at you... ah hmmm .... or go the easy way and get a strap wrench. Apply strap wrench, brace your shifter, twist in an upward movement and viola...off.
It's going to be putting the new one back on that's the problem. The Sonic's are all fitted on (not sure about RS or LTz, but I believe they are as well...just leather wrapped). It sucks, I know.