360 build

Have you looked at the Magnum create engines specs for the 300 HP unit? The almost laugable on how mello they are. But they make 300+ HP with nothing more than completeing the engine with headers and carb.

IF your short block is in good shape, all you'll for it is a 340 cam and complete the engine like above. I would mill the head a bit for better compresion. It would make the package more efficent and powerful.