A while back we debated what was factory on the AD/NP trucks on the radio speaker grills. I have recently aquired two parts trucks one a 1948 GMC the other a 1947 Chevrolet. Both had the original screens intact up to and including the press clips in the middle. These screens are a metal mesh so at least through 1948 it appears the factory screen was metal. Sometime in mid-49 I believe they went to the heavy muslin product. Please see the attached pictures for detail.
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