I think the only difference in the two is the diameter of the cam bearing journal.
The hemi and most all clone engines use a cam that is .005" smaller than the
non hemi engine. I have both, on different engines and that seems to be the only difference. They are not interchangeable. Call ARC like Hellion suggest. They are pretty good about letting you talk with one of their tech guys. I have called them
2 or 3 times, and have always received the information I requested.