You can buy weld nuts from McMaster Carr. They have a variety of types that would work. Or you can just weld a nut with the right threads to the inside of the cowl.
Weld Nuts


Kevin
1951 Chevy 3100 work truck
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Photos
1929 Ford pickup restored from the ground up. | 1929 Ford Special Coupe (First car)
Busting rust since the mid-60's
If you're smart enough to take it apart, you darn well better be smart enough to put it back together.