The two rubber mounts are inserted into corresponding holes in the radiator support on the driver's side of the radiator. One near the top; one near the bottom. The two bolts go through the driver's side radiator flange and into the rubber mounts. Tighten them just snug or the rubber mounts will pull back through.
I have one of the last of the NOS radiator supports and had to enlargen a pre-punched hole to get both rubber mounts installed. An aftermarket support might be even worse.
2012 Mustang Boss 302 #1918, Competition Orange. FGF replacement 2006 Mustang V6 Pony, Vista Blue. Factory ordered. 2019 BMW X3 (Titled to the wife, but I'm always driving it for her. So I'm claiming it) Old projects, gone but not forgotten: 1967 FB 400, original CA car. After 22 years of work, trashed by the guy who was supposed to paint it. I had to sell it. 1980 Turbo Trans Am 1970 Mustang fastback, 351C 4Bbl, auto 1988 Mustang GT, 5 speed 1983 F-150 4x4, built 302 1994 Chevy K2500 HD 4x4, 454 TBI