When I restored my '50 COE grill, I recall that the horizontal bars were stamped with a single digit, indicating which bar it was. Now this is a big bolt grill and therefore taller than yours, but constructed the same. I don't remember where on the bar the number was, other than it was hidden from the front. Look carefully and see it yours have a number.
Kent

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1942 Chevy 1/2 ton
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1950 Chevy COE Model 5700 ~ "Barney" ~ And more pix