check out this link http://www.warfs.org/content/view/61/63/

The translation is a bit dodgy but you can get the basic idea.

A mate of mine did a body lift on his suzuki using 2"box section which worked well and I'll be diong the same to my sportrak soon, as for the 31" tyre's I would be concerned with the front wheels rubbing on full lock but with a suspension lift, body lift and a few adjustments it should be ok. just remember to consider the legal side of any mods, unless like mine its just a quary toy.