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The correct approach to headliner installation on a classic car is methodical: rushing produces a result that looks wrong immediately and gets worse.
The original headliner on most American cars of the 1960s is a fabric-covered board — a hardboard or fiberboard shell covered with specific material, glued along the edges. The board shape is correct for the car; the material choice determines whether it looks right.
Installation sequence: prepare the surface of the roof structure — clean, apply fresh headliner cement to both the board edges and the corresponding roof structure. The cement should be applied to both surfaces, allowed to flash to a tacky dry state, and then pressed together. The alignment must be correct before contact — once the cement contacts, repositioning requires solvent and care.
New installations should be done in warm weather. Cold adhesive doesn't flow into the surface properly.