Brake Problem (long)

I recently inherited a series 1 E-type, the kind with two Dunlop brake master cylinders fed by little square bottles. It had not been driven for about two years, but started up fine and I went out for a short test drive. At first the brakes seemed adequate, but after a couple of miles, the front brakes started to drag and then got very hot (smoke from both fronts) and finally locked up. After they cooled I was able to put the car away, but there was almost no stopping power.

When I got the car back to my garage, I discovered that the aluminum tube that's part of the fluid level switch in the front brake reservoir had corroded and there were bits of aluminum floating around in the brake fluid. The fluid in the rear brake reservoir seems fine.

Here is what I have done so far:

1. Remove reservoir bottle, clean and replace.
2. Remove both front flex hoses.
3. Use Motive pressure bleeder to run clean fluid through the rigid tubes.
4. Replace rubber lines with new SS braided lines.
5. Use Motive bleeder to run almost a quart of fluid through the system and out the bleeders.

There is still no pressure from the master cylinder. When I try using the "pump the brake pedal" method of bleeding, nothing comes out of the bleeders.

I suspect that this means I'll need to rebuild or replace the master cylinders. I would appreciate any words of wisdom from anyone who has had similar problems.