Regarding the tires, I really have not noticed much change. I suppose it has decreased the speed by a couple of mph, but since the tire OD is only about 0.5" larger, it is not a drastic change. The big difference is that they are LT's and not P type, so the ride is stiffer as they are not as compliant, but that is what I want. They are also wider, so they handle the sand quite well, and they also are designed to be able to handle quite a lot of air down. Good tires!!!!
The Ranchos made a huge difference!!!! Good shocks are important, and they help prevent the infamous roll that the Exby's have. There are lots of discussions on the web on what are the best shocks to use (Edlebrock, Bilstein, etc.), but the Rancho' seem to be the easiest to get. I purchased mine from
http://summitracing.com/.
You are correct about the steering stabilizer. It is hard to tell if I the STB helps since the Exby's steering is soooo light, but its function is to prevent dampen rapid inputs into the steering system from the wheels, i.e. blown tire, ruts, bumps, etc. and since I do not notice them much, I guess it is doing its job. Its an easy install, and cost only about $60 if I remember correctly.