ROKRWLR brought up a good point. I've install a lot of these now and here are some tricks I use to knock the install time down to about 45 minutes.
For the drilling, I already covered the cheap bits thing. To make the whole process easier, don't do it with the jeep on it's tires and your laying on the ground. Get it up on jackstands or ramps, so you are sitting flat on your butt with your head in the tunnel looking directly at the end of the shaft. Thsi way you can drill directly into the end of the shaft instead of laying on the ground where you can't get a good eye on if you are drilling at an angle or putting angular stress on the bit. Let the bit do the work. Drill straight, and slow. If you drill fast, it just heats up and then it gets tough.
For the tapping, this will sound like a slow process, but it actually makes it go really fast with little risk of breaking the tap. have some cutting oil (motor oil works fine for me), the tap, and a can of brakefree on hand. Get the tap started about 1/4". Back the tap out, clean out the hole and the tap with the brakefree. add some more oil, tap in another 1/4". While tapping, I do one full turn in, back it out one full turn, thread back in and cut another full turn, back it out, etc., until you get 1/4". take the tap completely out, spray the tap and hole with break free to clear out all the debris. Continue the 1/4" cut and clean until you bottom out. The tap cuts very quick and clean when you keep removing all the garbage out of the way. Be sure you don't look directly at the end of the shaft and wear safety goggles when you spray the brakefree in the hole, because it will shoot right back out at you. I learned this once (stupid!) and that slowed the process down for a little while.
When you go to put the flange on, the tolerance is very tight. Have a fine grit triangular file and clean the burrs out of the splines at the end where you cut the shaft. if you put a drop light in around the shaft, you can look directly into the bolt hole of the flange and line up the splines just right. Slowly turn the flange lining up the splines until you find the sweet spot that the flange grabs on, then lightly slid it on. A small rubber mallot and some light taps dead center of the flange will help it go on. Don't force it on or get over zealous with the mallot, because then you will burr up the grooves, and the flange will stop, then you get to pull the flange off and have fun cleaning the burrs out of the splines. I have done it all, and it may sound like I just don't know what the heck I'm doing, but stuff happens that you learn from after doing so many, and hopefully my lessons learned will help others that have no experience keep from making this simple install into a nightmare.