The 130amp with 5 5/8" case is on the left. 95amp with 5 1/8" case is on the right. Note that the 130amp mounting bosses are at 12 & 6 oclock where the 95amp bosses are at 12 & 4 oclock. Also note the pully sizes, try to us your stock pully if possible, so you don't have belt leng