I have March Performance under-drive pulleys on my BBC, and I can’t find the proper belts for it. I have gone to the auto parts store three times, and I still haven’t found the right belt for the alternator. Parts stores are worthless if your application isn’t stock, and they couldn’t look it up on a computer. On the first try, I took cut stock belts and told the counter person at Car Quest to give me belts this long. He gave me belts that are too short. On the second try, I went to Kragen because it was Sunday and Car Quest was closed. This time I’ve staples to hold the ends of the belts together. The power steering belt came out okay. It could be a little shorter, but it fits. The alternator belt is the right length, but its too narrow, and its hitting the bottom of the pulley. It squeals like a banshee. I got the motor going and promptly blew the head gaskets. I then wallow in self pity. Sat on my ass. I pulled the motor, fixed it, sat on my ass, and reinstalled the motor. Then I blew up the rear end and replaced it. 19 months after buying the second belt-I tried again at the other Car Quest store. So onto the . . . Third try, I gave the counter person the second belt and told him to give me one belt a little wider and one a little wider and longer. He gave me belts that are too wide. Somebody told me automotive belts have classifications like industrial belts, but different. The belts I have are . . . Car Quest/Gates, 9435 13A1105, 15/32" x 43 - 7/8", This belt is too wide. Car Quest/Gates, 9440 13A1120, ½" x 44 -3/8", This belt is too wide. Kragen, 43013 321, This belt is too narrow.