pitman arm puller

Have a stubborn pitman arm but no one posts the opening dimensions. They may say for domestic cars and light duty trucks la la la. What I need is the part number of a heavy duty puller for my application. Working on a 68 Barracuda with manual steering. If anyone can respond with part numbers of their puller, I will search for one to purchase. So far, I have found OTC 8150, Snap-on CJ119B and Ferrum 0388. The latter two of the three may be too large but don't know. Thanks for any help.