1981 K5 305 with stock HEI coil in cap ignition. I have fire on two cylinders only. New HEI coil, new ignition module, new plugs and wires. I've performed the ohmmeter tests on the ignition coil and the pickup coil, even though they're new and both checked out. I have 12v coming to the distributor. New rotor as well. I also ran a hot wire directly to the coil from the battery just in case my supply from the ignition was dropping out under a load. I did just notice that my gas gauge, instead of reading the 1/4 tank that it has been, is now way over on the right hand side in about the 4 o'clock position. I don't know if that has any thing to do with it or if it's indicating a short somewhere that's affecting the whole system. What's going on?