Bleeding ABS Brakes

I was changing the brake fluid in my 87 300TDT (for the first time) and ran into trouble. I have bled brakes plenty of times before, but this has me confused. I bled the front calipers with my wife's help, no problem, but when I moved to the back, it seemed to be pumping air. I never got below min on the reservoir either! I applied a little air pressure (regulated at 20 psi) to the resevoir to try a make shift pressure bleeder, but it didn't do any better. I also disconnected the rear brake line right at the master cylinder and blew into the reservoir, and despite being full, it only gurgles, not a stream of fluid, came out the line.

This car has what appears to be an ABS system, not ASR. I also looked in the Mtc CD and I do not have the "y61" switch on the master cylinder and the ABS controller has "ABS" on it ( a Bosch unit I think).

I either tore up the seals in the Master Cylinder during the bleeding or I'm doing something wrong. Even if the seals went bad, I would think blowing into the reservoir would provide a steady stream of fluid at master cylinder exit port.

The CD does not seem to give any special requirements for bleeding the ABS brakes, only ASR.

I'm mad, my wife is mad, the dog is in hiding, any comments?

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Deezel
87 300TDT
150,000 miles