Read through the following thread and I think you will find what you need to know. Some good tips and part numbers. Hope this helps! In my case, I used the Dayco 15320 and found it easiest to take off the alternator pulley first as I was working alone.
yes on the 385hp part numbers for my 2000 SB. some of the available belts have inside cogs, some have outside cogs and some are smooth inside and out. i believe they will all work. i must remove alt pulley to install. any longer belt will not tighten enough. full slack hits oil pan and full tight hits frame with only ABOUT 1 inch in between. i have the factory v pulleys and for some reason have been losing alt belts recently with no apparent changes otherwise. i am having the squealing and may address later after resolving another more immediate issue.