I have a C model. I put 6 inch risers as well as R model handle bars on and kept the stock cables. I also have an ultimate big boy seat. I can lay back, relax my shoulders and still reach the bars.
I was told I couldn't use the stock cables but I have around 20,000 miles that says I can. You just have to swap sides of the frame with the cables. It did take me a while to get them routed just right and it may not LOOK and be right, but it will work. My .02