Looking at my 1971 factory assembly instruction manual (should be the same for 1972). It looks like the front bracket, Item 5, P/N 3932432, mounts to the head. I wonder if the BPE heads support this? View attachment 141104
Don't forget about the rear brace (#1 in the diagram I attached) that supports the rear bracket (#3 in your diagram). My Edelbrock intake mounting holes were a little off so the bracket needs some hole messaging to work for me. My 78 a/c attaches in the same manner as yours.