C3 Hood Mod

I have been toying with the idea of making a big block style hood from a mid 73 cowl induction hood. The illustration below shows what I am trying to do.

I would like to know how the experts here would do this. I'm thinking of cutting the cowl, backing up the gap with dense foam and shaping the front (the gray part). Then finish the surface and pull a mold.

Ideas?

despite being in fear of bannishment, have you thought about going through a vendor such as jc whitney and buying the style bulge you want and just grafting into your existing hood?
i would give other advise but my fiberglassing skill is the suck.