The screws easily and frequently break off while resisting removal. Drilling out the broken-off screws is a tedious operation. Steel bits won't bite into hardened steel screws and tantalum coated bits are no better. Carbide bits are too brittle and break, but we've had success with cobalt bits. In the case of the curved-steel ceiling, where the mounting screws will be covered by a wood molding, we did just make new holes.
Progress is slow, but steady.
We hope to complete this first interior side before fall. Hopefully our experience dealing with this first side will speed our progress on the other side, and we won't have to remove the interior paneling on that side. There is work to be done on the interior ends of the car, however, such as reinstalling the emergency valve wire, cord routing, and door hanging with molding work. Work has already begun on stripping paint in the right side smoker section. Note the roof cover area ready to receive a new curved panel.