I cropped in on this and hope it's clear enough. Basically the exposed front surfaces are argent silver. The headlight bezels are black between the fins.
Those are some beautiful darts! Now I want mine done!!!
Here's the grille I restored for my car... Be prepared for hours and hours of masking!!! I think most go with the 71 style grille paint for simplicity of masking.
My build thread linked in my sig has a lot of detailed pics of the grille resto as well.
Photos of the same grill. It the upper photo, the top is the original '70 paint scheme. The bottom is the '71 paint scheme. The lower photo has them reversed with the inset photo as the '70. The actual grills themselves are the same, fins painted silver or black is the only difference. The '70s have silver fins, the '71s have black fins. What will throw you off is if you search photos online, you will find Darts like mine which are 1970 Darts but with the 1971 style grill paint. I just like it better so that was my paint choice but it's something that a purist can easily change back when I'm taking my long dirt nap.
When doing the '71 paint scheme, I found it much easier masking to paint the silver first and then mask it and then paint the black last. I bought a masking tape at a Hobby/RC store that was the perfect width for the silver "bar" within the fins. I also refreshed the signal lights by repainting the reflectors at the same time.
Regardless of the scheme you choose, repainting the grill adds that final finishing touch. It really sets it off.