67 Valiant: brake problems. need help

If you can, "gravity bleeding" works pretty well. Just open the bleeder screws of the rear cylinders, top off the master cylinder, and let it sit for 15 minutes, check the master cylinder to make sure it has fluid, and watch to see if the fluid is dripping from the bleeder screws. If you have steady drips you can close the screws and try the brakes again. If not, wait longer, and check again, Hope this helps