Sounds fine .. It's 4 wires .. power, earth and then the two to interupt the signal from the gearbox.
My problem was I've got an Apexi RSM and it was working in MPH and not KMPH .. so my 0-100 was not a 0-60MPH dash, but a 0-100MPH dash.
And I don't wanna workout the distance it thought I was going for a 400m sprint

I've then realised that the RSM will de-limit and not effect the MPH/KMPH conversion. So I'm soldering that in instead.
It's all in working order .. well was befor I cut it out of my loom.
Let me know