I did it in 1980.
360 heads with a nice valve job. Never touched with a grinder. (Less)
DC 284/.484 cam in straight up.
Strip Dominator. Unported. (Less)
650 double pumper carb.(Less)
Hooker 5204 headers. (Less)
That right there is well over 300 HP and I double damn guarantee that that engine is easier and cheaper to build than what MI 318 is. ( You're such a superstar!)