six pack intake question

Yea I ran 390s and a 428. They were fun motors! Always liked Mopar and decided to give it a go. Bought a 73 Duster and a 340 to put in it. Then bought a 72 Duster for the 8 3/4 rear end in it. Found out the 72 was in better shape than I thought so now I am putting the 340 in that. I had been fighting with myself originally over whether to install a big block or small block on the 73. Since I will be putting the 340 in the 72 I figured now I have the excuse to install a big block in this one lol.