Product review (5 stars): Perfect replacement!
There are no instructions on how to replace the part, but if you are ordering this part you are fairly mechanical and it should take you about five minutes to replace it, that's including removal of the front cover assembly.  I have replaced this part twice so far, not from this provider, but I have owned the dishwasher for five years and it has broken twice.  If you buy this item as a replacement pulley you should be back to normal in no time.  Good luck