Product review (5 stars): Good improvement over factory piece...
I had already, previously replaced the factory plastic ones and they broke again.  The wheels just shear off from the cheap plastic clip holding them on.  Very poor, or deliberately poor, design by Kenmore.  The wheels on this W10712394 replacement appear to have an improved wheel attachment.  It's not the metal that makes this good, although that's great, rather the wheels themselves have a completely different, stronger looking connection than the Kenmore factory piece.

You need a torx bit or torx screwdriver or, as I noticed later, they include the torx bit that works with any Philips screwdriver haha. Nice touch.  You will only need a Phillips screwdriver to use this torx bit. There are just four screws with your new adjuster.  You also may need a flathead screwdriver to pop off the old plastic adjuster.  That's it for tools.  This kit replaces every piece holding the old adjusters on so you can toss the old junk away or keep it for a spare of either side is still good.

This was very easy to install. The instructions are dark and blurry but they are only two pages long and they did help get me started.  Look at my three photos. That's all you need to figure this out as you read the instructions.  There is another set of photos on here where the adjuster is higher than the top rack and it's not even clipped to the dish rack properly.  Mine are the correct placement.