It's do-able Frank. The seagull should be made from 1mm aluminium lined with neoprene on the underside. Then attached to the bottom of the Vee it needs a castellated W shape, also lined with neoprene. If the verticals of the W are in the same plane as the bonnets, it will hold them open, and this gizmo will slot on from the rear. Although you'd need to support one side with a stay in order to fit the seagull. All the weight would be taken on the insides of the bonnets, and the seagull wings would prevent it dropping down.
