Product review (1 stars): Same piece-of-junk design that you're replacing. Use W10712394 kit instead.
Don't waste your time and money this piece of junk. It's the same poorly-designed, low-quality material part that was in your dishwasher originally; and you'll be replacing it again within a year or so if you use this part (ask me how I know). Whirlpool / Kitchenaid should be ashamed putting such a poorly made design in their expensive dishwashers.

The better solution is to use the Whirlpool W10712394 Adjuster KIT. It is a re-design of the original adjuster setup and uses a metal piece in place of this piece. It is more rigid and does not use plastic "axles" for the rollers. It took me about 15 minutes to install the new part and completely replace the rack adjuster on both sides of the upper rack.