6.1 Hemi 69 Barracuda Fastback Father Son Project
Picture of my 73 C-Body (New Yorker) 1.25" thick x 11.75" Rotor on my 73 up A-Body spindle.
Got a pair of adapters for the outer bearings from Doctor Diff. (They're Not on his website, you need to email or text him.)

Had to remove a little material from the caliper brackets where the rotors touched. Marked in blue
Took off maybe an 1/8". It's a really beefy area of the brackets. The little material removed doesn't bother me.

Looks like this without the caliper.

Clearance of the rotor to bracket where I had to ground down the bracket.

I removed almost 2mm of friction material from the inner pads in order for the rotors to fit between the pads.
The inners were about 2mm thicker than the outers.
I put one side together using both outers and they fit fine, so decided to sand down the inners to the same thickness as the outers.
I did try a different set of pads that were the same inner/outer thickness, Bendix, both the inners and outers were interchangeable, all 4 pads were identical... I think the ones I have are Centrix but I could be mistaken. They came with shims on them which I removed which helped with fitting.
Hopefully will be able to get my calipers with the inlets on the bottom to work...
More research and test fitting ahead...