We took the sample outside and held it up to the big existing sign. Not to match it, but rather to see one colour over a big area rather than small sample.
The lightest, orangey one was pretty close to the colour there, and at that scale looked red. The impression I got was the other custom mix sample while it looks very red at a small size will look dark at scale.
…but, that was at night. That’s not invalid, but need to do this in daylight.
That is, if we are trying to choose a paint for everything, for the future. If we just want to paint a single sign, any of those samples might prove to be enough already and we can just get on with it.