I just wrapped up the last of my brake system repairs on my 69 F250 390 CS 4x2 front disc/rear drum. It was like peeling back an onion, layer after layer of rot. I honestly do not know how this truck stopped. The wheel cylinders appeared to have quit working during the Reagan administration, the pistons were seized to the bores on each. No leaks, honestly, how could it have leaked with them rusted shut? As for the rear brakes, here's what I learned for this model:
The wheel bearing retaining nuts are 2-3/8 rounded hex. There was evidence of them having been removed/installed with a hammer/chisel in the past. Buy a socket, they're cheap.
After removing the nut, the parking brake lever retaining bolt needs pressed out with a C-clamp and a socket, everything that comes apart there needs cleaned and lubed (I used CRC synthetic brake grease - gray like moly chassis lube).
Most brake hardware kits will give you green and red (or orange) springs to retain the shoes. The open end of the hooks on the springs should face each other, that means one red and one green for each side.
As for the front brakes. I was astonished how badly worn the rotors were, however knowing the rears didn't work I can see why. They were 0.100" thinner than discard, I think another 0.005" and I'd have seen fins. The caliper pistons had nearly disintegrated and only one side had bushings in the caliper ears. The right side was bouncing around in the cast ear sleeve. Poor workmanship during a previous repair, it had been pad slapped and sent down the road.
The bushings can be a challenge to remove/install. I wound up driving them out from the back with a bushing driver (Harbor Freight kit), then cleaning the bores thoroughly (so much rust).
I drove them in after assembling the boot to the bushing with the same driver. Greased it liberally and gently tapped it until the sound changed to a solid thud.
Then I used a 5/16" 3/8" drive socket to peen over the backside of the bushings (this ensures they won't walk out).
Pulled the rear bushings out with a large screwdriver and installed the new ones.
During the caliper installation (I bought loaded Raybestos calipers), I torqued the brackets to ears retaining bolts and nuts. Be careful here. Take a good, hard look at this hardware. Mine was Mickey-Mouse. I stretched the threads on the bolt torquing it to 21 lb.-ft. Ordered 4 more new ones, this time from Moog. Made of meat, no worries there. The ones Raybestos gave me were garbage.
Finally, the master cylinder. What a nightmare! How many different master cylinders are out there for this model? w/ Bendix casting, w/o, drum/drum w/power, disc/drum w/power...etc... It had the wrong master on it. It was a drum/drum master (with ZERO check valves) and a 1" bore. My first try was a Bendix 11779. WRONG. It was HUGE, I had to loosen the a/c suction line and reposition it to clear the master. I bench bled it, bled the whole system and had an intermittent soft pedal. It was internally bypassing. It was either mis-boxed or catalogued wrong (due to the size) and it was defective! I did more research and came up with NM1779 from Autozone (it's a new Cardone MC). Bench bled it, installed, and everything was OK. It's also smaller, however still ZERO residual check valve (should only have one in the front port - to the rear brakes). But it has a consistent and firm pedal. I've read that many aftermarket MC's are missing these nowadays. They were mostly for applications where the master was at or below the level of the wheel cylinders anyway. That being said, the new MC from Autozone had debris inside the fluid chambers, which instills much confidence. I flushed it with brake fluid, then bench bled it by pushing fluid into the bores through the ports and discarding the fluid a few times.
All told, the brakes are done, wheel bearings cleaned and repacked and the truck stops perfectly now.
Now to tackle the cooling system 
Happy Independence Day all!
Also the lube points, grease is cheap, it doesn't melt and when applied properly won't mess up the shoes. The other drum brake killer is disuse. If you drive it every day, DOT-3 lasts a very long time. If not, change it every 2 years like conventional green anti-freeze or else DOT-3 accumulates so much water it starts corroding wheel cylinders (among other components) internally, like mine were. I had to drive the pistons through the bore from one side with a large brass drift and suspension hammer. Took the hone to them and they were just too far gone. Terribly pitted. More into the scrap pile. I hope I walk out of the scrap yard with a wad of cash