Yeah... I have a '66 Toronado with the frame under the box. The dealer pounded on the arm till it came off, leaving a BIG dimple. The Shop Manual says NOT to do this, but...
I DO have two of the PROPER pullers, but need to turn the box, as you advise...
I bought a new Pitman arm from FLAP, China, $18, should last long enuff to sell it...