The holes in an original 400 bumper are not just drilled, but punched before chroming, and the stamping has a recessed area around the studs to allow for the slight swell where the studs are molded to the emblem.
Thanks for the detail, does this mean that they went through a separate stamping process compared to the non-400 bumpers?
1968 400 Coupe, verdoro green, black vinyl top 1968 400 Convertible, verdoro green, black top 1971 Trans Am, cameo white, auto 1970 Buick Skylark Custom Convertible 350-4(driver)