I remember there was a published article floating around by Gernold outlining the hardtop restoration (complete). Reading it convinced me that this was a very long term goal (read, years from now). Replacing headliner is problematic enough I think from reading that article that a full restoration of the hardtop might as well be accomplished. If someone has the article, perhaps they can share it with you (I no longer have it). Additionally, many have probably replaced the headliner themselves here, perhaps they can describe the bare bones needs and pitfalls (particularly with side windows and chrome trim) needed to replace just headliner. I have two hardtops, one sorry looking one here with a sunroof that I have disassembled to repair, and another one (original to the car that is on the car now in Canada) with numerous ugly stains and also a somewhat shabby painting trim on it. I am pretty sure that I will be trying the painting/staining, cleaning technique in the future as I see myself destroying the hardtop should I take it apart myself. The hardtop was well engineered (or surprisingly complex).
It certainly can't hurt to try a bunch of paints/stains on the headliner. That's my game plan.
1967 230SL