W124 seat covers, to hog ring or not?

[87tdwagen]

Hello all:
Curious as to what members have done when changing W124 seat covers, might apply to W126 as well.

The 300TD mbtex covers were attached to the horsehair pad via square shaped hog ring type fasteners engaging steel rods on the seat cover but only going thru the horsehair pad, not attached to any of the springs or spring box frame that I can tell. So other than tightening the center section to the pad, I can't see a purpose for these. The square fasteners themselves are not hog rings nor compatible with hog ring pliers.

I also understand that post face lift seats did away with the fasteners, but that could be to a seat redesign not sure.

What have you done? Did you reuse the fasteners, and if so how?
Some have suggested stitching with thick thread, did you attach to the pad only or to the spring subframe?

Did you skip them altogether as not needed?

Thanks