how do I remove/replace studs on 7 1/4

Doing a scarebird front disc swap so all of the front studs are now right hand thread, would like to replace the rear wheel studs so I have ALL right hand thread. How do I do this, is there a somewhat inexpensive tool, do I need to remove the axle? 67 Dart, 10 inch drums, 7 1/4 rear.
Thanks
Aaron