Steve,

What upholstery set do you have from JC?
The upholstery material?

The upholstery installation material/set (which is inadequate for a good/comfortable installation)?

What layers of material will you be putting between the upholstery and the springs?

Most likely you do not see any replies because people do not know enough regarding what you have. Foam was not originally used, so you will have to describe the layers of materials you plan to use (from the springs on up to beneath the upholstery).

Denny Graham posted a very detailed description of his upholstery work. Maybe he will post a link to that thread?