Mungolino, you are correct, one of the modifications to this car was the headliner (same as the sunvisors). The headliner should be leather, light cream color ('matching' the sunvisors) and smooth texture. Some cars did seem to have pleats. The leather is glued to the roof with a thin padding.
The interior trim frame that covers the seam between the leather headliner and the roof sheet metal is made of aluminum and covered in leather.
-Leather is applied across all the interior A pillars, and 360' along the windshield , side windows, and rear glass bow.
- the aluminum frame is also covered in leather. See detail of the back of the joint.
Interior leather used except for the headliner and dash top is natural texture, top grain without any artificial tooling (not "pebbled"). As I remember, the headliner is a smoother texture. Sunvisors are "basket weave" vinyl.
Sorry I didn't measure the frame (maybe someone else has their frame available to measure the frame)--Lee
