I'm a Polaris guy selling some stock a arms and spindles off of my father in laws 15 m6000 i was thinking they should fit a 12 hcr but I figured I could hit you guys up to double check before I sold em to this guy
They will fit but he's going to have to shorten his shocks the hcr has a 40in stance I believe and yours are a 38in. They make spacers you can put in the shocks I had to put them in mine when I switched to the 36in a arms