As reported in this excellent Road & Track piece, Ford entered a disguised aluminium-bodied 2015 F-150 in the 2013 Baja 1000 and finished the 1000 mile course without incident. To make sure nobody recognized the new truck, they stamped the 2014 body in aluminium. Genius. First, read the R&T piece for the whole story.
What's not told however, is that apparently the #227 F-150 was a DNF according to the official results here.
There is a good thread over at race-dezert.com with some first-hand accounts of the vehicle in
the race a different race. Of particular note is that the vehicle might have had engine management issues, was described as "glacially slow," and might have been involved in an strike with another vehicle that damaged a fender and thus outing the underlying aluminium body again, all occurring at a race prior to the Baja 1000.
EDIT: It appears that the Baja 1000 DNF was due to timing out; the Ford still finished the distance but not in the maximum allowed time. Engine management issues, "glacially slow" comment & body damage all occured at the 2013 Parker Bluewater Challenge, prior to the Baja 1000