I hang out on a couple of Ford Tractor forums.
Some times they go round and round about "correct" paint colors.
The original color of a 9N Ford tractor was a medium dark gray.
A lot of guys paint their 9N Red/light gray to look like the later 8N Ford.
Generally there is no issue with that.
Or Pink if it is for a worthy cause.
Or even Blue like the much later Ford Tractors.
And then there is always some one who paints his 9N to look like a John Deere.
That color scheme is almost universally despised.