I took my shifter knob off a couple days ago. I just took a pair of pliers to the base of the knob and twisted. It was hard to "break" at first, but it was easy after the initial break. I could not get it with my hand, but I replaced the shift knob with a bud light beer tap handle.
That should work for you, mine is a 91 that was poorly taken care of.
Threads are the same as normal, so put pliers and squeeze and turn to the left, it took me like 1 minute from start to finish, but that was because I didn't know if that was the way it went on.