FoMoCo seems to have used a lot of printed card board over the years. They usually had light colors with or without cross hatch lines printed on. Some may have been flocked like some other manufacturers but I don't know. Most were just stapled together. A lot of the folks that reproduce this stuff don't seem to care if it looks original or not. I guess they figure nobody looks in there or cares whether it looks original.
The 38/39 dash had a flatter front than the 40 did. If the opening is more square, one for a pickup might be adjusted to work a little easier. The little fasteners could be relocated. If Bob drake could make one then I figure anyone could if they got the right thickness of chip board.