So, lately I've been hearing this noise coming from my alternator that sounds like the bearings were about to go. Hearing that, I decided to order a set of underdrive pulleys and make project for myself. I took the old alternator off and just as I was about to pull the pulley off of the new alternator, I noticed that the pulley was the same size as the pulley that came in the underdrive kit. Has anyone else run into this? I thought it was weird, but it saved some time though.