We'll start in the back, as I mentioned, check the wheel cylinders, replace them if leaking or not free, do both sides not just the side with the problem, same with brake shoes, check for wear, if replacing the shoes remember the shoe with the most pad on it goes to the rear of the car. Check your brake drums, if they have wear, ridges on the outside of the drum, get them machined or replace them (They are cheap now). If you put new brake shoes on, machine the drums at the least. If the mounting hardware is original from 1971, replace the hardware (springs, pins and locks). If you replace or rebuild the wheel cylinders you will need to bleed the rear brakes...If you need help with this I can try to explain it to you when you cross that bridge.
Take off your front wheels, check the pads as to how much life is left. You can remove the caliper with the pads loaded in the caliper to get a better lock. This will also tell you if they are riveted or bonded...riveted pads have holes in the lining that allow the rivets to hold the pad onto the backing. If they are worn, replace the pads by compressing the caliper piston...I use a C clamp. If the piston moves back easily into the caliper and there aren't any leaks your calipers should be OK. Check your front brake rotors for scoring or ridges...if there are any turn (machine) the rotors or replace them, (there cheap now as well).
Hope this is what you where looking for