My pictures may be hard to completely follow along without a description. I did not attempt to repair the band; I completely
replaced it.
1. remove the old band completely.
2. Cut a heavy material to replace the band. I used a scrap of trunk liner (grab one for a couple $ at a junk yard if you don't have a suitable material) cut to about 11 x 13 inches.
3. Insert heavy duty zip-ties in all of the attachment points (around the metal rod).
4. Line up the material with the seat frame, mark then drill holes for the zip ties to secure it.
5. Put the material in place, insert zip-ties and tighten.
***note: I did add two additional holes for zip ties on the left and right side of the plastic frame.
Mine has held up well for 2 years and is a little more firm than the original.
I could send you a seat base from a '99 if Woody doesn't have one available. Good, but looks like partial cracking in the leather along the stitching in one part.
Here's pics of the one I will sell:
https://www.flickr.com/photos/126478035@N08/shares/768jf7