Righto, good ideas.
Yeah i have a head temp gauge. I went with the sensor that bolts to the head instead of a coolant temp gauge as it will notify me of temp regardless of what causes it - block rad, low coolant, low oil, failing fan etc.
I have one of these 3in1 gauges in my 4Runner, but i have oil, coolant temp and volts instead of EGT, Boost and volts:
3 IN 1 LCD DIGITAL 4WD GAUGE DIESEL EGT PYRO & BOOST & VOLTS GAUGE 52MM 7 COLOUR | eBay
It has been in my 4Runner which has been all around the southwest of WA up to Ningaloo, NSW and Tasmania and i love the gauge. The only negative to to the gauge is it wont auto dim for night driving you have to click the little button, cycle through backlight colours then to no backlight. So on short trips it is a pain but on long drives it doesn't take long to do.
On a side note, what do you get up to in your Disco your always tinkering with? You ever go out camping or exploring? Your up Queensland way right? That trip is on my list too.

