So I just got a used WRX. It had a crappy shift knob on it so I ordered a MOMO shift knob online. The problem is the old knob was held on by some sort of tape or glue. I have the knob off, but all this gunk is on the shift knob, its dirty, and won't let the new knob thread properly.
So far I have tried goo gone, a heat gun, and a razor blade and have had little success.
I get worried when I use the heat gun too much, as the entire handle heats up, and I worry about the transmission warming up as well. Any suggestions on what I should do, or if the heat gun is harmful or not?