I would like to add a extra rack above the rear bed.  There is one for the RZR 800 that bolts into their retention system.  Does anyone know if this would fit the zforce or know of anyone making one specifically for the zforce.

I don't know about racks. I do know the holes in the bed of the ZForce are not the same as the ones in a RZR. So, many RZR accessories would not fit.