Mine is 57.8in. I will use it just for the track. I have the Mac underdrive pulleys BUT I'm using the stock water pump pulley.
My routing is TOP of alternator ---*> TOP of IDLER---> TOP LEFt side of water pump (so it goes counter-clockwise..obviously)---> TOP RIGHT side of crank( so it goes clockwise)---> RIGHT side of tensionner---> and back to the alternator.