I don't have the answer.
But I can tell you that the seat from my 2010 RZR S 800 would fit, if I unbolted it from its base and bolted it onto the ACE's seat brackets.
But my RZR seat feels the same as my ACE seat so I wouldn't want to.
I bet your dealer would let you try it if you brought your ACE seat in.
But I'm also pretty sure that Polaris's price on that seat will probably be nearly as much, if not more than a really nice aftermarket suspension seat.
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