You'll be able to fabricate most of the missing parts for sure. If there's damage right on the nose that might be a little harder to shape, but should be doable. You'll need the repair section and some long strips of metal. I would get the repair section tacked in the right place, possibly with some temporary bits of metal to hold it to what remains of the bonnet, then I'd fill in the gaps between the repair section using a method very like the one in this video: