There has been so much discussion here that the real problem is getting lost.
After the tension "I" bolt to spring has been released and the belt has been mounted around everything except for the last pulley now comes the part where all the nice idea's are coming but the problem is..... you can't get to the pulley to stretch the belt around. It is buried under the battery box. You can't hardly see it, the spring, nor the eye bolt.
The way that the two of us finally got it on was with me in the back trying to slip the belt on the axel pulley while him buddy somehow got a hold of the tension pulley and pulled like hell. After that , we tightened the nut on the Eye Bolt for additional tension on the spring.
We did take off the nut from the eye bolt. (book said dont'). If we had I don't that we would have ever got it back into the position where it was. This is just one hell of a poor design.