no I think you re missing what I am saying.  The rotors are all machined to except the same race, seal, and grease cap regardless of weather it has a big axle shaft or smaller axle shaft.  What is different is the races and bearings.  Bigger axle shaft rotors, drums and hubs use a thinner race with a steeper angle allowing for the bigger ID bearing.  This is how I was able to take 67 Mustang hubs (small axle shaft) and install them on 72 Country Squire spindles (big axle shaft).  I simply replaced the races and used the corresponding bearings.

It sounds like the 69 spindles are small axle shaft so all you would need to do is get 72 rotors and then change out the bearings and races for the smaller shaft.  When I went to O'reilly auto's web site the difference in measurements  between the two years of rotors is with in .010" I am betting its the same rotor with difference races pressed in.  Ford would not have changed things so little to use different parts.  But manufactures could list different tolerances so people don't think its the same rotor and spend more on the "rare" rotor

I drove over to Illinois and took those spindles off this morning.  The guy had the car jacked up on farm machinery jackstands for me.   Went quick and painless.   I like it when they dont fight coming apart.    I can see why you wanted better looking calipers,  those are kind of ugly, with the weird metal clip on the back and such.  Rotors look like they are in decent shape, and the brake pads are brand new.   

The guy told me there was a story on the car.   It supposedly once belonged to Johnny Carson's mother.  It had some custom things inside it.  Came from Utah.   

mine were safety wired together.