1999 Ford Ranger 3.0 idler pulley

I recently changed out my idler puller because of a squealing I thought it was making after changing my alternator and serpentine belt. {This is the idler pulley I change, not the tensioner pulley.} When I took off the pulley there was a washer on back that has to be screwed off and a plastic looking bushing that sits inside of the bearing. When I went to replace the new pulley I noticed the washer that goes on the back of the pulley has protruding inner edges on one side. Which way should the washer go. I put the plastic looking bushing back inside the pulley bearing and put the washer with the protruding inner edges toward the pulley. I then fastened the new pulley on and bolted it in place. I didn't notice the way the washer was facing when I took it off. Was this the correct way to do this. Thanks for any HELP. {It still squeals. Maybe the belt tension pulley needs replacing} Anyway, did I put the washer with the protruding inner edes on correctly? Thanks for any and all Help.