Just finished doing this about 2 months ago:
YES, you will need to remove the ring gear. This is not that big a deal. You simply remove the bearing caps, being sure that you keep them straight, which is not hard as there are usually marks on the caps and on the diff to line up. you then remove the carrier using 1 or 2 pry bars and an extra set of hands. You don't have to worry about shims, because they are under the bearings. Take the carrier and put it in a vice. remove the ring gear bolts. Install the lock right. put the ring gear back on, torque them down to spec. Put the carrier back into the diff, put the bearing caps back on the right side and torque down the bolts - I think 57 ft lbs on the bearing cap bolts. I'm not sure about the ring gear bolts, But I can look it up if you want. The hardest part is getting the carrier back into the housing, at least for me. This took a couple pairs of hands, a piece of wood (to place against the bearing race to hammer on), a hammer, and some very gentle persuasion.
Once you install the lock right you will see that it is MUCH easier to do on a bench than trying to do it with the carrier in the housing.
Once you've done it you'll think "What has I worried about?". Of course, all this means you have to remove the axles first. To do this you will need a 13 mm 12 point 1/2 drive socket and perhaps a pry bar to remove the hub bolts. Be sure to never seize them when putting them back.
The other bit of advice I have is how to install the inner passenger side axle. This took me forever until one day I figured out the trick. You put in the inner axle until it rests against the side gears of the lock right. You then put a pry bar in the outer end of the tube and ON TOP of the end of the inner axle that is outside of the seal, so you can push DOWN on it. You use your fingers as a 'fulcrum' in the center where the disconnect vacuum motor is, and use the pry bar to push down and raise the end of the axle that is against the lock right. If you don't do this, you will not be able to get enough leverage on the axle at the vacuum motor to raise it high enough to enter the side gear.
Anyway, I've had my front diff apart twice now in the last 2 months, and I can say it is not that difficult. email me for more instructions or a phone number and I can talk you through it if you want.