Looks like Brian called my problem correctly, the master rear brake reservoir being empty. Question now is, once I fill that, can I get away by just bleeding at the two rear wheels or do I need to first bleed the line/fitting at master that goes to the rear? Then, after that, do I need to also bleed at the ABS unit and if so, where? Lastly, since the rear brake reservoir is separate from the front reservoir, will I need to also bleed at the front wheels?

Also, Paul brings up a good question as to whether there is a proportioning valve in that rear line and if so, what is its effect on the bleeding operation?

Thanks
Bill