Brake bleeding problem/question

I am bleeding my brakes now and I have a problem. I have done all the wheels starting with the passenger rear, then driver rear, passenger front, and I am currently on the driver front. The first three wheels went fine, all air out. Now on the driver I am encountering a problem. I cannot get the air out for the life of me. Also when I pump it fast it seems that the brake fluid is becoming agitated and has many small bubbles in it. Also from the cabin against the firewall where the master cylinder is hooked up there is a strange almost gurgling sound. It is odd that the first three went fine and this front driver side wheel is giving me the problem.

Please, any recommendations would be helpful. By the way I am using a Granada setup with a Wilwood Proportioning valve and a 74 Maverick Master Cylinder and speed bleeders on all four corners.

Is there a seal in the back of this MC that where the brake pedal push rod could have messed up? Where is this air coming from?

So I went out to get some new fluid and attempted to bleed the brakes a little bit different. As of this evening I have great clamping power on the brakes but there is definitely still some air I have to rid the system of.

Fastcoupe, I did bench bleed the MC, but I my partner while helping me bleed the brakes allowed the MC to run dry so I think that may have voided the effects of the bench bleed. As for the speed of the pumping of the pedal I think you may have gotten that right on the head. I started to slow down on the pumping and it seemed to be much more effective. There is definitely still some air stuck in there. I am going to try to get rid of that tomorrow hopefully.

Mustang70, initially I had my friend watch the MC, but he let it get too far down so now I am watching it. It hasn't gotten down since I have been watching it, but it is normal for the MC to almost "geyser" while pumping it occaisonally right? I assume that is just air escaping the lines/MC.