I was going to ask what type of front drive shaft mods would be needed but that all depends on whether I just go with the 4.70's in the stock transfer case or go for a dual case set up.....
if you went 4.7s with a stock case you wont need anything. maybe just upgrade it with a stronger/more spline driveline. i know trail gear makes one with long travle splines....
with duals you will have to shorten yours. when i did my duals i took my driveline to DriveLine Tech. The guy owns the shop all by himself and does amazing work. he made my driveline out of .250 DOM. strong as you will ever need i payed 200 bucks i think and i gave him my front driveline i had from my IFS cause it had a CV and he put the CV in the rear cause its a Short Steep angle.
