Hey did you figure out the routing? I have a 2010 575 and I routed it down seat tube, along rear break cable by BB, and up the underside of downtube with other cables. Stock cable was perfect length for me. I used zip ties to anchor the cable at certain points to keep the cable from bunching weird when adjusting the seat. Hope this helps.
Installed a Reverb on my 2011 575 and it comes with a cable guide to attach to the seat tube. I ran the cable up the left side and attached a stick on cable guide to my rear shock. The '11 575 has a cable guide on the left hand side near the steer tube. Two things to watch for. If you run the cable too close to the middle (centerline) of the seat, it will bind up on the seatstay and get caught in your tire. Second is the Reverb comes in a left or right hand remote. Mine came with the left hand side and was too long. I cut the line to length and bled the line after, and it works like a charm. Best upgrade I have purchased in years.