Actually a little more hunting and I found this pic.
So typically people take the giant squared vent and just mount it ontop of their hood with rivets. Personally I'm not a fan of that.
So by making a tight template of the raised bits of the actual vent and mounting it underneath the hood, protruding outside, you can simulate a different look from it
- a better one in my opinion.
He has it still mounted with rivets (big silver ones) and I'm on the fence at this point if I want to go that route (small black ones) or find an alternative to mounting.
The differences in paint on the hood and vent still make it stand out more though.