I have a copy of wiring diagram for the dealer add on turn signal ,,its for the "guide" set up that went on the '54s and '55 first series.
its for the one that actually belongs there,,not the "yankee" or "turnco" aftermarkets.
If youd like to give it a try,,i'll send you a copy. P.M. me with your address and its in the mail to ya.
Marty