No, unfortunately they aren't. There is a bearing out there that will fit in the recess in the end of the crank and allow you to run a 4 speed behind a crank not drilled for a pilot bushing, but I believe you have to cut a little off the end of the input shaft of the tranny. If I remember right the bearing is available from NAPA, but I don't have a part number. Chryco Psycho or one of the other folks on here might though. If not, then go over to moparchat.com and post it there, and someone will come up with the part number. That is where I read about the bearing.