Switching from Paul C Buff lights to any light brand that uses the Bowens mount means either buying new light modifiers or converting existing modifiers. The less expensive approach is a mount change. In this case, the Buff light modifiers offer the ability to remove the Balcar flange and replace it with a Bowens flange. In this video, you will see how to do it.
It’s possible that the size will be slightly too small for the Buff modifier. If it is, I recommend using washers to fill the gap and make the mount strong. Otherwise, there is a risk of disconnection.