That belt has a couple twists in it. you"re pretty close.
keep in mind, the 2 idlers. the V groove one gets the V side of the belt in it, the flat idler gets the flat side against it. then just twist the belt so its on the other two pulleys and spins the blower the proper direction.
Its hard for me to explain, but I"ve done so many, my hands know how to do it easily. my brain isn"t quite as good at it lol.