It is possible to connect a rev counter with a MVT ignition but it needs a model 4-stroke at induction.

Indeed a MVT DD or PREMIUM ignition has 2 sparks per revolution and a 2-stroke rev counter would double the actual measurement (the 4-stroke model divides the measurement by 2).

Then do not directly connect the rev counter to the high-voltage spark plug wire because the ignition generates 42 KiloVolts to the spark plug and there would be too many electrical noise to make the measurement. It is necessary to connect the rev counter on the Orange wire of the primary circuit which goes from the Diagram box to the High Voltage Coil.