I talked to my dealer about that very thing yesterday. He said that they can be made to fit, but it takes some modifying of the steel seat tray that the factory seat mounts to. I assume that that means drilling some new holes in the correct locations. He offered to do it if I wanted one instead of Deere's suspension seat, but I passed.
Yes, I did put one on my z950. It is easy to do but will have to drill 2 new holes because they do not line up to the bolts in the michigan seat. Then you will have to add (4) spacers on the seat bolts before mounting onto seat platform. The spacer are roughly 1/2 inch or so just to clear the platform. I bought large washers at ACE hardware to do this. It will be easier just to take the whole platform off the machine to drill holes and mount the michigan seat. I think the black seat looks much better than the yellow seat. Plus a better ride at a cheaper cost than the John Deere suspension seat kit.
I've tried the Michigan seat before getting a Grammer seat from Ebay, IMO a better seat.
BTW, it is installed in a '10 Snapper Pro S200X with a 32hp Briggs Vanguard plus the cost for the seat still about $800.00 cheaper than the JD that does not come with a suspension seat and about $1500.00 than an Exmark with suspension, both of those with a 60" and 29 Kawasaki engines.
i sat on a michigan seat on a super z the other day. it felt really comfortable and it would be nice to have one on my john deere. i don't have the john deere suspension seat i just have the normal seat with no suspension. it's ok but the michigan seat would make it ride like a caddy.