Do you want to keep the 31's or do you plan to go bigger? As for the lift.. look over everything really well before you remove the body lift as things like wires, hoses etc might be at their max length or have been modified to get the 4" body lift on. Over all I think a 3-4" suspension lift will work out best. Depends on how good or bad the body lift was installed, you may find you need to have some body lift in there as a result of that install, thus no more than a 1" Body. As for the SYE skip it for now and just lower the t-case skid.