a rigid snap - on plastic cover for a sun - damaged vinyl - covered dashboard pad is installed in an automobile without loosening or removing the dashboard pad from a dashboard substructure . the snap - on cover is made by draping a preheated softened polycarbonate sheet over a mold positioned on a narrowed support . a partial vacuum is produced in the region covered by the draped polycarbonate material , causing it to be drawn against the mold for support and to conform thereto . a skirt portion of the polycarbonate material from the support is severed after the vacuum is released , and the forward portion of the hardened polycarbonate is lifted over the mold , forcing any breakage of the &# 34 ; back draft &# 34 ; portion of the polycarbonate to occur in forward corner locations that will not be visable when the snap - on cover is installed in the automobile . the peripheral portions of the polycarbonate material are cut cleanly away and the outer surface is spray painted . the cover then is snapped into position over the vinyl covered dashboard pad in the automobile , after applying glue to the inner surface .