Two basic options and there are not really any "kits".
Granada spindles and calipers - have that on my car - alignment is a nightmare plus other specialized items like the front flex lines.
The easy route - Scarebird brackets on the OEM spindles. Believe you can get a complete list of items needed for the Scarebird brackets by joining the forum (it's cheap) Send a message to Simplyconnected - one of our admins - he has a ton of info.
More than just adding the disc's though - booster, lines, new master cyl etc but with either option you will need to change wheels. The center hole on the OEM Ford drum wheel is too small to clear the rotor snout. I used 70's Ford LTD 14 inch wheels but there are other options.
Search the site on Disc's or Disc brakes for a lot of info.