Pulley Alignment

I did spin the Alternator by hand before installing. No noise. Never been used or installed before. 1st fire the whine was present immediately. Could I have the wrong belt? Would a belt with too much tension automatically destroy bearings and create such a whine?

Also, got pulleys and the bracket coming. When searching to buy a new belt online can I just buy one for a 273 and be safe in size?

Am I going to have to get a single groove alternator for these new pulleys?