60 TBird vacuum assist brakes

Hi Guys

My name is Marcus and I am writing to you from Iraq. I am getting ready to rotate home and want to get my 60 convertible Bird back on the road.

Here is my problem.

My brakes are on a vacuum assist system ever since I had a new vacuum booster (the big round thing that the master cylinder is bolted too) put on the car the brake pedal is extremely firm when pressed and no matter how hard I push the brakes never seem to brake any better. I have nearly rear ended several people due to this problem.

If possible could you give me a trouble shooting guide to work through this issue?

So far I can tell the car is putting out of about 20 PSI and the vacuum canister appears to be fully intact. I have already changed the rubber vacuum hoses. I have also had somebody check the master cylinder reservoir (top off) when I push on the brake to see if fluid pushes out (it does). If I push on the brake with the vacuum line detached and then connect vacuum line the brake pedal does move ever so slightly.

Any help would be appreciated.