GR8,
On my '74 the BLUE with BLACK stripe wire was the tach lead.
I mounted my MSD on the engine side of the pass firewall just over the metal strip where the coil and regulator were mounted. I remounted the coil there, but went to a one wire (internal regulator) alt. The MSD has been mounted there for years with no problems. I heard no buzzing or whining coming from the radio, so I didn't need a noise suppressor, but I did need a tach adaptor.
Michael
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