I am having a problem putting on the drive belt for the above mentioned riding mower. I have been able to get the new belt around the small pulley that is above the large blade pulley (coming out of the engine itself) but I cannot get the belt to the axle pulley or the idler. There not enough room to do anything even with the mower deck all the way down and when the clutch in pushed in. Is there a "magic" part of this process I'm missing? I;m about to follow the so called owner's manual and take to whole thing apart... any help would be great.

Do you have the manual, if not open this and put your cursor over the belt area, it will enlargen it. http://www.searspartsdirect.com/partsdirect/part-model/Craftsman-Parts/Riding-mower-tractor-Parts/Model-502256210/0247/1506000/10052297/00002?blt=06&prst=&shdMod= Sounds like you did most everything. It siometimes takes a second pperson to pull back on the tensior pulley. It has a strong spring which pushes the belts from the flat side. Tensioner pulley is part #55, in the picture it is smack between the two larger pulleys but you need to pull it towards you, towards bottom of picture so the belt is making an oval rather than a backwords letter B