X350 owner here, but came across a listing for a reputable U-Pull It lot I frequent in Philadelphia area, Pic-a-Part Barbie (female-owned business).

Yesterday on FB, they posted that a 1987 XJ (I assume XJ6) 4.2L black with gray interior is new to the yard. They never give details on parts available, but this place is small and tucked away so you may get lucky if you are looking for parts on this gen and do not mind pulling yourself.

Located outside NE Philly/South Trenton area- you don't have to go into the city as it's in an industrial part of Morrisville... between 295/195/95. May be worth the trip, as I imagine these don't show up often.

https://www.facebook.com/share/p/1CspeTdpaL/

 

Good "heads up". Wish it was in my area.