You will need:
- A pair of scissors
A roll of red electrical tape
And one beer (I prefer craft because I save so much money doing my own repairs)
Now just take a thin strip of red electrical tape and go ahead and extend that little red zone down, waaay down to where it belongs. On mine I've had an infared heat gun on it enough to know roughly where I should start being concerned about the temperature.
Now go enjoy your beer, and if anyone else is driving your van (you shouldn't let anyone besides yourself drive the Delica, but sometimes it happens....) they should at least know if it's getting too hot. You will hopefully have an Exhaust Gas Temperature gauge as well, and remember every dash temperature gauge will read a bit different!