I dunno, sounds like a lot of work to me. You might be happier changing the rear gear or maybe looking into a Ranger or Gear Venders overdrive. Running that aux. trans backward may not give the performance that you want. Plus you will have all the extra weight added. Not saying that it can't be done, the theory is sound. You will be making the trans runnung in a direction it wasn't designed for, you could end up damaging it or the truck.
