I have done a bunch of them, both by replacing the entire tub, and just replacing the bearings and seal. Both take about the same time, and personally I find replacing the bearings and seal/shaft is easier. You must have the tool to press the new bearings in. The tool basically self aligns the bearings. There's hardly any way you can screw it up. I actually installed 1 bearing kit on Friday at work, and 1 on sat for a friend. It takes me about 35 minutes to complete the job. The part supplier I use is Marcone and they sell the bearing kit part #w10435302
for about $55 bucks. Here's some tips that help me complete the job
1. Tape the lid shut.
2. Pull all parts of tub assy out before leaning the machine back to get underneath.
3. Remove motor assy. Loosen the nut on the spin shaft, and wack it out upwards with a hammer.
4. Set machine back down, i use a big flat blade craftsman screwdriver and pound the lower bearing out first.
5. Tilt the machine again, and pound the upper bearing out from underneath.
At that point your done taking apart, and just reassemble. There are instructions in the box.