I have an MSD6AL on my '79 Spider. It is triggered by a 123ignition distributor. I have the stock tachometer connection - no adapter, resistor, diode needed. I time my distributor at full advance at 4000 rpm and it is fine. I did not notice any funny stuff due to the multiple sparks at lower rpm but I was not specifically looking for anything unusual.
76 Suzuki GT500
2011 Jaguar XKR
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