Waja MMC and Campro will have two connectors to the meter cluster. If I remember they are blue and yellow. I've changed my MMC meter to Campro and its nice. The connector matches perfectly. The only thing is you need to connect a 600ohm resistor to the temperature sensor as they are different. Everything else is ok. Its definitely kewl.
Sorry, I was supposed to add more.
The only way to find out is to use a multimeter and read the reading of the pins one by one. You can ground the black common wire to body. Put the car in idle, then disconnect one connector. If the connector you pulled out caused the tacho to drop, then that connector has the wire for tacho.
Then for every pin you test, rev the engine. The pin that reads up and down (as you rev) is the tachometer pin.
