Amazon is the best price I've found for the belts. I replace them 1st thing on the 4 (5th was a parts junker) 'wings I've had. BTWm Comstar (78-79) wheels have the speedo drive on the leftm spoked on the right. The FSM has good assembly drawings of each. Also, follow it when mounting/tightening the bolts there is a sequence that must be followed and clearances measured at the calipers.