Freightdriver, your conversion to front discs has as many options as an engine build. Whose master cyl are you going to run, MP, Wilwood, Master Power, SSBC? Everything you need is readily available, but the decisions are many.
If manual MC, the bore size has a big effect on brake performance (hydraulic gain). I run a Wilwood w/ 1.03 bore, with their adjustable prop valve on the rear line. (The Wilwood prop valve starts at about 55% if I recall.) This is with their 4 piston ProLite calipers front and rear.
The line size also effects response, because the fluid travels "farther" on a given application in a smaller line than in a larger one. This, combined with the swept volume of the pistons (2, 4, or 6) in your calipers will determine how the system performs, along with the pedal ratio and the MC bore.
Note:Power brake cars need to have the pedal assembly changed to the manual brake configuration (see service manual), removing the extra linkage that reduces pedal leverage to the power booster/MC. To set pedal height with an aftermarket MC, you'll also need an adjustable pushrod, available as an MP part (Mancini, Jims Auto Parts,..).
Finally, don't scrimp on the plumbing. Use new lines, hard and flex, with a new master and calipers. See Classic Tube or Inline TUbe for their catalogs of fittings, lines, tools, atc.
Best of luck, brakes are the most challenging (you live or ??) and rewarding to upgrade.