What do people think of running a different width belt? No matter what I do, Im getting just  a horrible squeak noise from the rear pully when I'm under power, when I'm in neutral or with clutch in, it goes away.

Ive cleaned the pully, Ive tried reseating the belt, Belt Conditioner seems to work, but only for a trip or two, then I have to reapply. Its honestly driving me to look for other bikes, its just one battle after another with this..

Something isn't aligned just right, if everything is where it is supposed to be it won't squeak.  

Best regards,

Belt tension and alignment are key.  Search the forum, there's a lot of help with both.  How many miles on the bike?  You may need to replace the rear pulley bearing.  It's not hard to do.  Search for the double bearing fix.

check to see if you've swapped spacers.
fat one on the left, skinny on the right.
the fat one fits into a seal, the skinny one slips in last.

Front pulley comes loose too