Those of us who grew up looking at oscilloscope patterns can recognize an original equipment GM HEI ignition module just from looking at the primary waveform on the scope. When the coil reaches full magnetic saturation, the module kicks in a "current limiter" that creates a step in the horizontal scope sweep partway to the equivalent of the "points open" part of the sweep where the coil is supposed to fire. Since that limiter incorporates some fancy (translation: E$$$PENSIVE) electronics, most aftermarket module manufacturers don't bother to include it in their products. Original equipment Delco-Remy parts are good. I don't like the recently-made stuff that's labeled "AC-Delco"- - - -guess where it's made?
Jerry

"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln
Cringe and wail in fear, Eloi- - - - -we Morlocks are on the hunt!
There is nothing noble in being superior to your fellow man; true nobility is being superior to your former self. - Ernest Hemingway
Love your enemies and drive 'em nuts!