Look around and get the best shop you can for gears. Buying you own parts is a good idea, a shop will almost always markup parts costs.
Bottom line, the money is worth it. 4.10's rock! I've installed at least a half dozen sets of gears in 8.8's, and I still spend about six to eight hours doing it. It takes awhile to check bearing preloads, pinion depth, backlash, etc... The labor cost is high for a reason. The key is to find a shop/person that is willing to spend the extra time to do a good job. The little details is what prevents gear whine/clunks/leaks/accelerated wear.
Never did Lt's on an SN-95, but I know for a fact its time consuming on a 5.0 fox. I'm guessing your's will be the same/worse. It doesn't really require special tools or equipment, just a good bit of time and patience.