I have a 91 yz 250 and need the radiator louvers. My part number is 3XJ-2172A-00-00, a 92 is the same. My question is whether or not a 93 model with a part number of 4EW-2172A-00-00 will be compatible. Is the 4EW just a designator for the model or is it a completely different part. Thanks!