83 Delta Brake Issues

Hello all. Am having trouble getting a good pedal on my Delta. A little history. The right front caliper stuck a few months back. Got smoking hot, had to get a tow. Replaced caliper and repacked wheel bearings, they were fine. Then the car felt like it was pulling to the right when brakes were applied. So I changed the left front caliper too, repack bearings and bleed brakes. It seemed okay but the pedal was not like it was before. I would stop at a light and the pedal would very slowly go down. So I took the front wheels off and rebled the front brakes with a handheld vacuum pump and the little cup attachment. I took maybe 8oz of fluid out of each caliper. The Master cylinder did not run dry. Got in the car and no pedal at all, so I parked it until a friend could help. He came over yesterday and we rebled the fronts, lots of air bubbles came out. Again took out about 8oz on each side. The pedal is still quite low and now the brake light is on. I read on the AutoZone site that a pin has to be held in on the proportioning valve to bleed properly. I did not know this, it was not done. I'm not exactly sure what to do next, did my master cylinder give up? How do I get the light off? Do I just hold that pin in and rebleed? Where is the pin located? This car does not have the PowerMaster system. :crying:

First make sure there is no way air is getting into the system, bad hoses/rusted lines. Second if the pedal slowly sunk to the floor this is usually a m/c problem. Yes the prop valve button needs to be moved to bleed the rear brakes more effectively, especially with a vacuum bleeder.

Replaced master cylinder. Pedal is better and firm as well, not quite high enough, I'm going to check the back brakes for clearance, they don't seem to self adjust very well even though I have disassembled both sides before. If I can get the brake light to go off, everything will be okay I think. One tip for all you guys out there, if you have a GM car with an angle cylinder you need to raise the back of the car up for bleeding, the MC needs to be level.