HELP drum to disk break swap lower ball joint same or diffrent

Hey , I might as well jump in here too. NOS Mopar joints have the same forging number regardless of whether the're for drum or disc application.The early, '72- mounting holes
are 3 3/4" CL-CL The one in the picture with the pimple on the side, looks to
be a '73+. Those measure 4 1/4" CL-CL. Early drum brake joints have 1/2" mounting
holes, and those for discs are 9/16". I wouldn't advise drilling them with a standard drill
I use a 4 flute core drill, (drills much more accurately). As someone said, its your steer-
ing.