i have a 47 shorty with the small exciter ie no auxllary 110v power i have feild coils and a new exciter arm to do this upgrade but the feild coils dont fit in the housing my old ones are about half the size as my new ones lincolin used to have a kit to upgrade these machines mine is a code 671 i would think i could find a spider bracket some where since lincolin used to make the kit the kit number was M-6878