I have taken down part of the headliner in Stella Blue to inspect and repair the mast base mounting hardware. Here is how I reinstalled the fabric.

First I made an installation tool from a putty knife. I rounded the corners and polished the edges smooth, so it would not cut the fabric. I made a much larger radius on one end.

The track is a very tough nylon which is has a very tight channel for the fabric. You need a tool thin enough to separate the channel and slip in, but stiff enough as well. The putty knife worked pretty well after I got the hang of it.

They say a pictures worth a thousand words, so I'll let the pictures do most of the talking. Below is a section that has been partially tucked in.

By pulling the fabric across the track and using the tool to push it into the track, some excess fabric still remained outside the track. This is not a problem and can be tucked in later. By sticking the square of the tool in the area that is already tucked in and then rolling the knife (from right to left below) use the large radius on the putty knife to gradually push the fabric into the track.

After I had the headliner up and tucked in place, I started back at the beginning, tucking the excess fabric into the track. I found that doubling the fabric back on it's self, and pushing on the vinyl side, made progress much easier. The knife will grip the vinyl much better than the cloth backing.

The headliner back to its original condition