It has a 1" neck which fits a Shovelhead stem - that's why I fitted the Shovelead forks, that and I wanted some brakes! When we fitted the rear mudguard it became obvious that the position of the crossbrace was wrong, and it has become increasingly apparent that the various forgings in the area behind the seat post are missing. In short, the bike seems to have a fabricated back end.
This all makes me suspect it is a fabricated unit based on a Servicar front, because the backbone forging and seat post base forgings are certainly there.
Anyone have experience of such a thing?