What sort of tacho do old datsuns run

[mikec(nz)]

I am trying to get my tacho working in my 240K running a MSD unit.

Seems I need a tach convertor, but not sure which type as it depends on the type of tacho the ol' Datsun runs

Options are

1. Current triggered
2. Voltage triggered
3. Magnetic triggered

Some say I need the PN8920 which implies magnetic trigger but others say the Datsun tachos changed later in the '70's

Any accurate advice would be appreciated

Cheers

Mike

[mikec(nz)]

Just had some feedback that they are magnetic, Will purchase the PN8920 and see if it works.