Finished the install on my 67 K20. New MC from Napa, (matched Delco-Moraine to the booster) Dual chamber booster & P-value from a 72 K20, new lines to a '75 Dana 44 Disk brake front end. I've bled each rear corner 3 times, the fronts 4 times. Getting clear brake fulid from all with no bubbles. Still have the warning light (even after trying the reset button) and the pedal only gives goes down about 1/2 inch and is super hard. Vac line is hooked into the manifold, running the stock 2 barrel, on the stock 283. What am I doing wrong here?