Brake upgrade on a 65 cuda

Don't know what the Scarebird kit (s) cost but why not use factory 73 thru 76 front disks? You can usually find a complete set up for sale with a little patience and you can even upgrade to B body 11.75" discs with the correct caliper adapters and rotors. You will need the large ball joint upper A arms, spindles, rotors, calipers and adapters. This will also give you the 4.5" bolt pattern. Just did a quick search for "mopar disc brake conversion" and got pages of offerings. I did this to my 65 Cuda years ago. It's all a bolt on swap. If you specify '76 calipers you will get a 2.75" piston which are larger than the earlier years.