We went with a rebuilt hydroboost unit spec'd for a '82 K20, a new AC Delco master cylinder for the same, and a Wilwood adjustable proportioning valve. The rest of the system is copper-nickel lines, SS hoses, Wilwood D52 dual-piston front calipers, and JB5 rear drums.
We whipped up our own mounting bracket to utilize the stock bolt pattern in the '65 C10 firewall. The pedal was modded slightly to place the hole in the correct location for the hydroboost pushrod. A little tab was added to actuate the stock '65 brake pedal switch.