I have a '03 400S and I'm looking into changing the carb out. It seems every one is happy with the Keihin 39mm FCR. My question to those that have done this conversion is it worth just buying it from tt store or piece it together and try to save some bucks. I think that buying it from tt might be more expensive, but then won't have the head ache of trying to track down parts. Any sugestions welcomed.