W140 screw threads in upper front door sill
 

I just noticed that there are threaded holes in the upper surface of the front door sill/jamb of the S420. Follow the sill/jamb up the A-pillar, there's a screw, a seam, then two treaded holes about 60 cm apart. My car has these holes on both sides. I didn't ckeck the rear. Are these for a roof rack?

Thanks,
Sixto
95 S420
87 300SDL