I have a question on a 1931 4 door Sedan front seat back cushion. It appears that the cushion spring is attached directly to the wood sections of the seat framework that includes the bottom and steel back of the seat. So the seat cushion can not be removed from the seat framework after it is installed. Is this correct? The other three seat springs in the car have wood attached to the springs and can be removed from the car by themselves.

You are correct. The seat back cushion on the front seat of the 4 dr is attached permanently to the seat frame. The spring is held to the wood frame with loops of material around the spring frame tacked into the wood. The upholstery itself has a lower white linen panel that is tacked at the bottom of the wood frame than the top of the upholstery is tacked into the top of the seat frame. Wire-on is then tacked into the edge of the frame to cover the edges of the upholstery.