First a single reservoir in the master cylinder, than a dual one, front brakes were separated from the rears. Currently using diagonals, so rr, fl, then rl fr is the proper sequence.
Have to those reservoirs full, with ABS, if air gets into the vanes, you really will have problems. Best way with ABS was to hot wire the ABS pump motor, with it running, just open the bleeder, into a collector of course, would only take seconds. Not so nice guys at GM want us to buy a way overpriced scanner now to do the same thing, don't give a dam about maintenance. Pressure bleeding is out of the question was to easy to put air in the system.
Vacuum bleeding is best, but should remove each bleeder first and coat the threads with Permatex non-hardening gasket maker, hardly no fluid will leak out, and this way you are pumping out fluid instead of air. Clear tube is necessary so you can vacuum until it comes out clean. I use a Mason jar, punched two 1/4" holes in it and soldered 1/4" tubing into the lid just to the bottom of the lid, no deeper.
Pumping the brake pedal will put those two O'Rings in a territory they haven't been in for years, may find you need a new master cylinder, can't buy those square O'rings anymore. Want to sell you a new cylinder for only $$$$$$.
Those steel clips are a PITA on the pad brackets, if in a road salt area trap salt, corrosion, expansion, and jam the pads so they cannot return to the home position. This is the first step, remove the brackets wire brush them clean and coat with anti-seize, should be able to replace the pads with your fingers. Can't do this without removing the wheel, also a good time to bleed the brakes.
