68 Barracuda grill insert colour

Hello. I am an Aussie & have a 68 Formula S 340 Barracuda Coupe
I am in the final stages of my resto & am trying to determine the colour that the plastic grilles should be. I am aware of where the black paint is applied But cannot determine what colour the rest of it should be.
Can anyone on here shed some light on the colour?
I have attached a couple of images of it's current state
Cheers, Glen

Cuda 020.jpg

Cuda 021.jpg