If you find a carb shop that knows Q-jets well (and yours hasn't been butchered up any thru its last overhauls), they will have all the stuff to properly rebuild these...meaning yes, they will have the reamer to rebush the base plate...There was a guy up here in Whatcom Co (Sutton Carburaetion (sp)) that knew these carbs in and out, and was the king of dialing these in, but he has moved on to bigger and better things, as the carb rebuilding business just ain't what it used to be 5-10 yrs ago....