I have an EF wagon and an EF sedan here, (I know that isn't XF) but they both have numbers stamped on the end plug of different values, the wagon also uses different ports to the sedan. Never noticed the piping difference till this topic evolved.
Lionel, if you'd like to email the scans to me at
gary@comdotau.com I can host them on one of my sites and post the results here in jpg or pdf as the crowd prefers.