I really don't know the answer to that. My gut says no, they won't work. BUT, to be sure, I would call Carl's in Idaho and ask them. They came off of a 685 that they built.
You would need to ask Carl's. Just tell them they came off of Erin Bukleman's 2007 685 IQ RMK sled. They built the sled so they ought to remember. Let me know if you need me to call for you...