Hello rwinlkleblack,
You will need a pitman arm puller (special tool) & you may need to unbolt the gear box from the from to get it on the arm & an impact in there.If you cannot get access to a puller,you can use an a small carbide wheel cutter & cut a slot in the arm.If you choose to do this be very careful not to cut all the way through & not to cur into the gear housing or pitman shaft.The puller is the best way.
Master A.S.E Automotive technician
A.S.E MasterTechnician A1-A8 w/L1,38 years experience General Motors Master Technician