Flathead screw driver, and a 1/2 ratchet works like a charm no need to cut the belt off. Put the screwdriver between the crank pulley and belt and just rotate the engine over. The belt is made to "stretch"

 

X2 thats exactly how i did mine on my old truck no problems and no cutting the belt! i agree with the SHITTY design though. i remember lookin down there and thinkin uhh wheres the tensioner, how the hell do i get this thing off lol