Silicon spray works well on the header Dave. Less messy than grease.
When my seal separated at the corners I used a roll of neoprene to hold it in place until the glue set. New seals have a ribbed finish.
My big problem is that I love the look of the hood cover, but you know what a pain that is to fit and remove. I don't like to see a furled hood laying naked on the rear panel. But I like that better than no visible hood with the trad stud hood........