I just had a clutch/pp/flywheel/slave/master change. I didn't notice it when I drove away from the shop until a little later, but when the transmission is in neutral I hear a chattering noise coming from the trans tunnel.. Is this fairly common on these clutches? My guess would be no, but I was wondering if anyone else had this problem.

 

Upon closer inspection, it would seem I'm an idiot

It was just the exhaust rattling on the trans crossmember.