Electrical Installation ?

Ok my brother has a Suzuki GS 500 bike, he's went and purchased a device
called Gear Indicator by Biketronix. The manual says it should take about 30
mins to set up. He's been at it for just over a day now. The manual and
website say that you have to use certain coloured wires for certain
connections (obviously) the problem is that the device supplied has 4 wires
of colour Black, Red, Green and Yellow but the manual keeps mentioning
orange and blue wires from the device but as I've said it doesn't have an
orange or blue wire. The main problem he seems to be having is finding the
pulse input from the tachograph/speedometer. Can any knowledgeable soul tell
me on which loom he'd find the pulse from the tacho/speedo? also will he
require a multimeter? I've provided a link to the website so you can have an

I would love to help but my GS has mechanical clocks.

Bwaahahahahaha! Please, please, please tell me they all do, and that a
retard has just wasted his money.

My HBoL only goes up to '02 but makes no mention of electronic clocks.
I suppose it is possible that they threw away a perfectly good proven
mechanical design and installed expensive electronics but it would
rather fly in the face of the cheap and cheerful philosophy that
characterises the range.