I have laminated a couple of layers over the existing steel roof, and I plan to cut away all but two inches around the perimeter. If I glued the composite roof to the flange first, it’s sure to fit, but then reinforcing the ceiling would be awkward. I was thinking a big X shape foam core going cross corners would be a good shape that would allow for helmet to ceiling clearance. Without the car upside down, laminating over the core seems too difficult. I’m nervous to reinforce before gluing the roof down, for fear that I twist it enough that it won’t fit. I’m open to all suggestions.
Aesthetics is not a consideration. I’ll deal with it later.