B9 Side Skirts - clips - bonded or screwed?

[VeeReihenmotor6]

Hi,

I have a "sport" model without side-skirts. The facelift A4 sports seem to have the side-skirts fitted and look much better to my eye.

I'd like to have some painted and fitted, looking at the parts diagram it looks like they are bonded as well as fitted to clips. Couple of Qs - are the clips necessary and are the clips bonded or screwed into the sill? I don't like the idea of screwing in outside of factory build as it could become a rust trap, any advice here please?

Parts diagram, unfortuatnely no part number for the clips.

https://www.lllparts.co.uk/catalogs/audi/RDW/A4Q/849/8/853/853001

Thanks,
Matt