| Fitted mine this weekend, and it wasn't too bad.
I read a little tip on a website somewhere that you should fit a little push-button (push to make, not a toggle switch) to the blue "program" wire rather than keep touching it to an earth point. This makes sense as once you've programmed the unit, you can change modes with the switch (ie, on the fly!) rather than keep touching the wire to earth.
Once the switch was on, I connected the program (blue) and earth (green) together as this is what you need to do.
I then found that the three wires on a plug going into the back of the tacho are the three feeds (+ive, earth, sense) that you need, so I popped the plug, removed the metal connectors from the plug, soldered the RevLight wires onto the metal connectors and popped them back in! Easy!
The RevLight is mounted at an angle across the top of the speedo and the light cluster at about 30-40 degrees. I've hot-glued it in place at the two points and feels really solid. The button is mounted on the top, making it easy to switch modes and program.
Pics to follow!  | 
antonye
Threaded Mode