Recently purchased this 1998 XJ8 and looks like either a lower grill or the fin is missing but can’t tell which by the brackets. I believe the bumper was replaced after a minor accident. Can anyone identify which part I’d need? Thanks!

 

"Radiator Grille Vane," HNC6881ACXXX (new, primered). There are some on eBay, search HNC6881AC.

 

Alternatively (as opposed to buying the OE replacement part) the sky is the limit when is comes to actually improving on the OE design of that plastic part. Below you will find a picture of what I did there (where your part is missing) on my S-Type (I even wrote a Guide about of how to do it - I can send the link, if you are interested...):


I especially like the "special touch" of having a leaping Jaguar where a Mustang or a Ferrari have a horse...