I am new to all of this and need to order some more blades for my mower. I have a John Deere 727A Z-Trak ZTR w/ 54" deck. I want to order blades from J Thomas. They weren't any help so I'll ask you folks. Do I have a mid-mount deck or a crank deck? Those are the only two options for J Deere 54" decks. It should seem obvious, but after talking to the gal who answered the phone at Thomas she seemed to think I had a crank deck since cranks are held on to by chain links. Thank you.