Mine was frozen solid too when I pulled the mast. 3lb sledge, a LOT of pounding, and a small propane torch finally did it. With the hammer, I hit the pin back and forth (Port/Starboard) until I got it to budge a little in one direction. Once it moved, it didn't take much to get it the rest of the way.
I boogered up the old one so bad that I had to buy a new one from Bud. I slathered it with Tef-Gel before reinstalling.