Hello. I have a 1980 Trailcat 4000 with a mikuni butterfly valve carb on in. When i first go tit the carb was shot. Tried to clean and the long thin pipe with hole sin it that goes down to the main jet was cracked and bent. Had to put a 3000 carb on. I want to use the size carb that the 4000 was meant for. Does anyone know where to get these obsolete mikuni butterfly carb parts? Also what size jet could i use on this carb? the hex jets i can order from denis kirk? what sizes should i get?