I have almost a complete kit to convert your 1965-1966 mustang front drum brakes to power disk.
What I have is a set of SSBC 4 piston calipers with pads, splash shield, power booster, dual master cly., brake lines and all mounting hardware. Missing are the caliper mounting brackets available at NPD for $52 each (PN 2B135-1A and 2B134-1A) and the rotors. This kit sells for around $1150.00. Asking $500
All of the above part are new and still in plastic.