Mushu absolutely adores Smokey, he follows him around and tries to copy things that he does. Its adorable and I am so glad they get along. My concern though; when they are playing Mushu seems to get over excited and gets rough grabs Smokey by the neck. He doesn't drag him or anything and Smokey doesn't scream or soil himself, just kind of makes a squeaking noise that sounds almost like a dookie. When Mushu gets to this point I usually intervene and put Mushu in the calm down corner for a few minutes and soothe Smokey.

What else can I do? Should I be doing anything? Will Mushu likely grow out of this as they are together more/as he gets older? They have only been together since Monday.

 Sounds like Mushus just wants to play.  As long as their is no screaming, or scared poop. I would just key eye on them.  If you do get nervous....just break it up and put their attention some where else. No, need to punish Mushus....they are just being ferrets.

Sounds like they are playing/establishing dominance! My boy was like that when I first got my little female...he annoyed the CRAP out of her, and she was always running away and hissing at him. After about 2 weeks, they figured out how to play/get along, and they are now inseparable. :) 

They usually go back and fourth like this till mushu lays on the ground panting. But lately it feels like they're conspiaring against my home work

So i have noticed something i gave the two a bath together earlier ans sincw thwn Mushu hasn't been so rough does it have to do with the fact they smell the same now?

could be.  one recommendation for introducing new ferrets is to give everyone a bath.  Whatever the reason I'm glad they get along better

THE DOOKS OF HAZARD