During winter months of driving it is possible to install a shorter belt on a SN95 Mustang to reduce drag. This eliminates the drag created by the idler pulley and the A/C pulley. During Summer months (left belt diagram) when A/C is needed a 89 inch belt can be used. During Winter months (right belt diagram) however, a 80.2" belt can be used and is fairly basic to install.

A few pictures of the winter belt installed: