Sounds like you either replaced the bad part with another bad one or didn't find the problem yet. I would check the ignition fuse with a test light first, if that is ok check for power at the coil. You should have constant 12 volts at the coil with the key in the run position and in the start position. If you don't have power in both positions the problem is between the ignition and the coil. If that looks ok put the light on the other coil lead, it should blink or strobe when you are cranking the engine. If the light doesn't blink the problem is something in the distributer or ignition box.