302 Heads on a 273

Edelbrock made the street master, single plane small runner low rise.
Edelbrock also made the sp2p, dual plane micro runner pos that keeps it from making more than 250 hp.
Holley made the Street Dominator and the strip dominator. They both worked very well.
Fwiw Casting number 920 heads have about a .67 cc Chamber The last set I picked up were redone once and they came out to 66.5cc. So that tells you they had to be bigger from the factory. Now wither or not all years of those of heads are 67cc
Is a good question. Always check.

I don't recommend running adapter plates from two Barrel to 4 Barrel, ultimately it will only flow what a 2 Barrel flange allows it to and not realize the full cfm potential of the four barrels.