I know this is not what you asked, but unless money is no object or you want to change ratios a lot you really should consider a Dana 60.
A 9 inch can be built to be as strong as a Dana but at more expense. While heavier the Dana will probably be at least as fast, maybe faster because it takes less horsepower to drive it.
I am no expert but I have researched this earlier. My personal experience as many others on this board has been to switch from an 8 3/4 to a Dana and not slow down a bit. The added efficiency of the Dana makes up for the additional weight. An 8 3/4 is more efficient than a 9 inch. That being said I think there are some really high dollar 9 inch center sections with special gears that relocate the pinion and make the 9 inch very efficient.
