I have had good luck pulling pitman arms (and other tapered shafts) by using a 2 pound hammer and back-up hammer. Hold the back-up hammer against the arm and hit the arm directly opposite of the backup hammer at an angle perpendicular to the centerline of the sector shaft. You won't be able to go all the way around, but do as much as you can. Switch the backup and hitting hammer positions. This procedure will make it a lot easier for the puller to do its job. Usually I can hammer on a stubborn pitman arm for a while and pry it off with a screwdriver if it does not fall down by itself.

Remember 9-11-01--God Bless the USA
JUSTICE, not REVENGE, will prevail

1951 Chevy 1/2-ton Pickup truck