how much of a job to replace carrier bearing in jeep?

It will be for the home mechanic. The whole differential will have to come apart. Special tools and measurements are needed for install.

However a 4x4 shop and most mechanics will have the special tools needed to get the job done rather quickly..

It is not hard, but a bit of work. You will need to pull the axles and diff cover to start. Once you get the carrier out, unless you have a clam shell puller, the bearings will be a pain in the rear to get off the carrier. You can cut them off with a cut off wheel.

The get the carrier out of your jeep, put a wrench on an upper ring bolt and use a pry bar on a lower bolt to pry it out. Or you can rent a case spreader to make it a tad easier.

Yes it is.

Look up the part on Rock auto.com. It may give you more info on there.