I have acquired a very nice set of pipes and mufflers from a 1980 CB 650 custom and would like to put them on a 1981 standard. In the parts fish the parts for both years are the same... but the standard and custom are different as they of course have either 4 or 2 mufflers. The custom set are solid from headers to mufflers while the two center headers on the standard are separate from the muffler and are held to it by clamps. My question is does anyone know if the 4 into 4 will bolt to the standard??? I really hate to disassemble the exhaust system just to find out they won't interchange.