Since we are on the subject of seat springs, I have found that in many cases the front seats are too soft. I put a new interior in my Town Sedan. In the process, I took a close look at the seat springs and put some stiffer coils from an old rear seat bottom that I got at Hershey. What a difference. Now I was sitting on top of a comfortable seat instead of "inside it!" Take a close look at how the coils are wired in place and how they react when a load is placed on them. It doesn't hurt to have additional retainers to keep the coils in place and vertical. Also, do a good job of spray painting them for long life. Ed