I take it
That you are referring to needing brackets for a 71, correct? That would mean that you could use a bracket for a 70-71 Torino 429 or a 71 Mustang/Cougar. That's gonna be a toughie (tuffie?) tuffy? toughy? Well, you get what I mean...
Sorry, can't help you here. But you might try Mustang or Torino sources...