Marc Datzkiwsky

I need the audi part numbers for my 2013 A-5 2.0 L quattro underbody panels and frame that holds them. Its three pieces under the front of the car. Could I see an Audi diagram with the parts and numbers.

SMac770

parts.audiusa.com would be your default go to, but navigating it to find the right diagram can sometimes suck. Often because things are simply not there. They've really screwed it up with the presentation change; annoying to use now.
ETKA (the parts catalog the dealership uses) clones like www.realoem.me/Audi/USA and nemigaparts.com/cat_spares/etka/audi/ are more complete, but it's still a parsing many pictures to find the necessary one. Their search never works, at least for me.
Go to Body for your country/model/year, then search the page for bumper or noise or underbody, depending on which diagram of parts you're looking for.