A 15x10 wheel / 28x10.5S slicks with decent (i.e. NO rubber or polyurethane bushings) solid adjustable uppers, lowers, spherical housing bearings, and double adjustable shocks combined with a housing that can handle the power is all you would need. 7's and 8's are fairly common with that setup nowadays, so 9's would be no big deal. Maybe a little bit of control arm mount bracing on the frame-side of the uppers and lowers to keep them from moving.