I want to fit one of these TIM gauges to my MK1 http://www.potn.com/tim_c5201_3583.htm, and I was just wondering how hard it is to fit. I was looking at some instructions for other gauges and it doesn’t look like too much of a big job.

My questions are does it simply “plug in” to the ignition system or what?
I realize I need to get to the instrument wiring, can I do this without taking the dash to pieces? (I’m presuming these gauges are illuminated and so need to fit to the lighting cable) Where is a good earthing point near the dash?

And finally why is the 80mm dial
http://www.potn.com/-_c5201_3583_p1816023.htm

cheaper than the 52mm
http://www.potn.com/-_c5201_3583_p1816022.htm

What am I missing here the bigger dial is cheaper than the smaller?

Thanks for any help anyone can give.

the tim gauge is pretty simple to fit cant go wrong just test the wires going into the coil pack as they rnt the same colour as it says on the instructions.