Audio Systems: Car audio noise, spark plug wires, custom autosound

Question
I have a 1962 Corvette that I installed a Custom Autosound USA6 AM/FM digital PLL radio. No CD player, but, installed Autosound kick panel speakers and dual coil speaker in dash. I also installed a new antenna and antenna cable and all new grounds. When the engine is off the radio works perfectly. When the engine is on I get FM static, AM is useless. The frequency of the static increases with RPM. A new small block engine has been installed. The old stainless steel ignition shield has been removed. However, the spark plug wires are the noise suppression carbon core spiral wound type and I encased each with aircraft braided shielding and grounded each. I built and grounded an aluminum shield around the distributor and coil. I put a filter on the alternator out put and antenna cable in put to the radio. The ignition is MSD multiple spark with induction trigger in the distributor. I put a MSD noise suppression filter control box power leads. None of the above had any effect. I installed a inductive/capacitive filter on the radio + & - power line. That reduced the noise about 1/3. Power is via the original radio wire through the fuse block. The radio memory power is a jumper from the electric clock power with no filter. Any idea what to do?  

Answer
That stainless ignition shield is your only savior. It is mandatory on those fiberglass body vehicles. The aluminum will not block the RF the way the stainless steel will. You will never be able to eliminate the noise, but the original steel cover will make it bearable. Also, remove the antenna filters, as they will just reduce the radio's effective range. Other ideas are lining the underside of the hood with steel mesh,and grounding that, and wrapping the radio harness with metal and grounding that also.