Well, I made up my mind, and bought the Wilwood front disc brake kit for my 59 (# 140-13653), I am not ready to do the install yet, but in looking over the instruction sheets, there was no mention of what Wilwood recommends for a master cylinder, or a suggested bore size.
Lynn, I checked out the 67 Galaxie manual brake master cylinder that you suggested, but at least according to Rock Autos website, it is for use with power brakes, and the only manual brake application for a 67 Galaxie I could find, was for 4 wheel drum brakes. Do you recall the bore diameter of your master? Did you 67 Galaxie master cyl. come with the pushrod? A power brake application would not use a pushrod, as there is a pushrod built into the vacuum booster. A friend gave me the like new man. brake master cyl. that he used on his 64 Comet, when it used to have Wilwood front discs up front, but retained the rear drums. It has a 15/16" bore. I may give it a try. Also, did you use the recommended Wilwood braided flex hoses, and if so, what length did you go with? I figure I may as well install a Line Lock and adjustable proportioning valve all at the same time.