I need some help with finding a good way of tapping in an external rpm instrument into my 944 S2, euro model. The instrument can handle the signal from a hall sensor too, but I don't know if that's the most convenient way of doing it. I will use the instrument inside the car, so I'm also considering the option of tapping into some kind of tacho signal wire. Has anyone done this and know which wires to use?

I'm not that good with electronics, so I'm having a bit of trouble reading the workshop manual schematics. http://www.cannell.co.uk/944_worksho...electrical.pdf