need advice on raising back end of 05 Rincon 650

We own a 2005 Rincon 650. It has 27" tires on it and the 2inch lift kit. The problem that we are having is that the back end only has like 1 inch clearence from the wheel well. I am researching this for my finace. I would like to find out if heavy springs rating or shocks would fix this problem. And surprise him. Any ideas?