wiring these in...
basically, the dials are powered by an inverter... the inverter is powered by any 12v supply, obviously, you only want the inverter to be "on" when the lights are on...
SO...
heres where you wire the pos and neg from the inverter... any switch in your car that lights up when you turn the lights on will have a grey/green wire, or a grey/blue wire... every one, the headlight switch, window, mirror, heater controls etc etc, this is the pos, and all these will have a brown wire... the earth, you can splice the pos and neg into any of these, and it will work perfect, OR you can find a pos and neg on the circuit borad and solder the pos and neg from the inverter to the board, so the clock can be removed if needs be as one whole unit. EASY

sorry if i offended anyone, but 4 pages of people either saying they cant afford these or there not worth the money is pointless, these dont get made in MPH, this i why he has sorted a group buy, there are no other dials like this out there, with this kind of selection available, the only other plasma dials like this available are DDI dials, and they come in at about £110...
on the subject of showing both KPH and MPH, well, its up to you really isnt it, but i can name a butt load of companys who offer dials throught the uk with only MPH readings... Premier dials, DDi, Lockwood, etc etc, if you MOT'er moans, then take it else where, as if hes gonna fail you for that, then your gonna fail where ever!