Hood Inserts For '67-'68 Barracudas

We are building a 67 convertible with an s car anti sway bar, 1967 cast 340, 68 340 s inserts, and several other 1968 parts partially due to we like some of the 68 parts better and the 68 150 mph speedo was easier to get than the one year only screw on 67 speedo. This car was a base convert 273 2 bbl and they do not sell for anything like a Gen III car so why not "improve it" rather than keep it original.