I own a 2001 721d with a 2001 "9561" 61" deck. I've beat the 2001 deck up pretty bad and it needs a lot of work to go back to work.
I recently bought a 2007 727k2 with a 2007 "3461" 61" deck and I put that deck on my old 721d.
I have a couple of issues and not sure how to overcome these issues...