Pad make a huge difference. DO NOT use parts-store OEM metallics with manual brakes if they did not come with them from the factory.
You can also get a $40 brake pressure gauge from summitracing to check the pressure at the bleeders. You should get about 600psi on that car @100lbs pedal load with manual brakes. If less, suspect a restriction somewhere, and check that the metering valve stem moves outward while braking.
http://www.babcox.com/editorial/bf/bf50014.htm (about 3/4 down)