i have a 1970 nova ss with power brakes disc/drum and recently replaced the master cylinder (bench bled ) and bleed all the brakes and can not get rid of the idiot brake light? i pulled the pressure diff. switch and noticed a brass rod inside and did not notice anythig else in there, is this correct?? before removing the switch, i would put my foot on the brake pedal and the rears would lock up and would not get any in the front. this prompted my removal of the switch to see about resetting.