There are several ways to go about this, I used this kit http://www.jbconversions.com/products/dana300/plate.php
and their 4:1 kit. I didn't turn mine up flat, just halfway up from stock. "Worth it" just depends on your use, less lift and more clearance. You'll have to modify your skid plate or build a new one to take advantage of this.
'81 Scrambler w/ FI 360 AMC, 33x12.50 BFG M/T's, 5" of lift, ARB'd Dana 44's F & R, Dana 300 clocked & twin sticked w/4:1, Warn XD9000i, etc...
2002 Grand Cherokee Limited, 2008 Overland Grand Cherokee, a 1976 CJ-7 in pieces and 3 more off-brand 4x4s...............