Had the same set up. Tried the MSD tach adapter also. Could never get it to work.
Went to Pantera Electronics ignition controller. Works great now.
I made the mistake of pulling out the coil wire from the distributor cap to turn the engine over without it firing.
The coil threw a lightening bolt about 12 inches and just missed me.
Forget the MSD. It's complete trash. Get the Pantera Electronics unit. You will love it.
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