1971 Duster Twister Rallye Wheels without Center Emblem?

The only place that you see a ralleye wheel without the center cap is in the 1970 sales brochure. The folio was designed before the center caps were available so they showed a bare rim in the brochure. I think that the Twister ringless wheels were the only place that happened. Later Darts, Dart Sports, Dusters and Scamps with ralleye wheels all had brushed stainless trim rings, with the later center caps.