I just had to deal with this LAST night.
A good friend of mine kept insisting his way would work. Well, after trying his 'ways' for over 2 hrs, I did it my way, and an hour later, they were out and the new ones were going in.
They easiest way to get it out is using a sawzall. Be careful tho, as it is easy to cut into the bracket on the axle. Sharp blades help tons. Cut thru the rubber and sleeve between the arm & the bracket on the truck. It took me about an hour to cut both arms out.
Burning them out won't help you if the sleeve is froze on the bolt. It will just get rid of the rubber, and it may weaken the axle brackets. when the mess is over, the sleeve will still be frozen on the bolt, and still in the brackets.
Good Luck !!!