C'mon Peter - if they can do a bathroom reno within 30 minutes on a TV show, it can't be that hard, can it?!?
I bet your instruments will end up better than mine. I have all brand new Autometer Ultralights. Here's how they work:
Voltmeter - reads 0.5V high
Tacho - generally 200rpm out
Fuel pressure - not liquid filled, so flutters between 40 and 50 psi at idle when the pressure is a rock solid 44psi
Oil Pressure - reads 10 to 15psi low (scary!)
Odometer - I'll let you know if I ever connect the speedo cable
Speedo - As above !!!
Boost - never looked at the gauges when the engine is making boost - too many other things happening...
Fuel level - Bloody hopeless. Reads full for 5 minutes after I fill the tank, then it falls down to around 1/4.
Lucky the gauges are cheap. If I were doing it again (and considering my lack of interest in attempting to make Cobras look authentic), I'd use a Motec backlit dash. Stack also make a nice dash.