SN 28xxxxxxxx271

I'm looking for help replacing the drive belt. I've searched and found a few tidbits on how it's done but I still need some help.
I can figure out how to remove the belt on the pulley below the blade but the part of the belt that goes around the pulley on the rear (transmission) has me baffled. There is a guide of some type above that rear pulley and I don't think I can get the belt between that and the pulley. What bolts to I need to remove to get the belt on the rear tranny pulley? I guess Toro/Lawnboy no longer makes service manuals for their mowers anymore because I couldn't find one to purchase either.