I have purchased a used 2007 Jaguar XK and I am wondering if anyone has ever dropped in a newer Mustang GT 5 liter Coyote V8?

 

The new AJ133 and the 5 litre Coyote have the same bore centres and at one time before Tata Bought Jaguar there was talk about making the better flowing GDi cylinder heads of the Jag fit on the Coyote engine. So in all likelihood it will physically fit. Good luck in getting it rigged up and running with all the electrics, modules and control systems and getting the instruments to work....