The quickest, and safest fix will be to ream the Pitman arm and steering arm to fit the tapered studs on the new drag link. Try Victor Machinery Co. for a selection of reamers that will match the measurements of the studs on the new drag link. They're pretty good people to deal with, even if they talk a little funny ("Noo Joisey", I think!)
www.victornet.comJerry