Digital Tachometer Installation on M42

[1point8litre]

Hi guys. I ordered a digital tachometer to use with on my M42. I know that under normal circumstances I could get a tachometer converter and use a regular aftermarket tachometer, but I wanted something small, square and subtle.

The important details as I understand them are that it accepts a 5v pulse signal. But I'm not exactly sure where to get it. Is it as easy as using the engine speed pinout in the c101?

Here's the item: https://www.amazon.com/DIGITEN-Motor.../dp/B018S87WVU

Here are the electronic details:
Power requirement:DC 8-15V
Measure range : 5-9999RPM.
Clear zero: Automatic
Clear zero time:about 10s.the greater the RPM value,the longer the clear zero time.
Refresh frequency: 0.2-0.5S@120-1200RPM;0.25-0.06S@2400-9999RPM.
Measure indication:RPM<5000,¡À2;RPM>5000,¡À3.
Display:blue 0.56 inch LED
Input sign:Pusle signal,wet contactor signal,PNP or NPN proximity switch,HALL sensor.
Dimension:72x36x20mm,panel cutout Dimension:68x33mm
Operating temperature: 0 to 50¡ãC.

Thanks in advance for any help!

[Gregs///M]

Black wire is the engine speed signal. You can find it at the round plug under the hood, diagnostic port. You can also find at the DME or in the blue cluster harness.