Most of us who run a centrifugal super charger add an idler pulley between the alt and p/s. Just wanted to share a good pulley I found with a double bearing so it will last longer. It also has a snap ring to retain the bearings so you can change them easily instead of replacing the entire assembly. lji372 sells the stand-off that you need to add the extra pulley.

https://www.ebay.com/itm/Dayco-89105...-127632-2357-0