You should check the frame number on your TT as well. Swapping out engines was a very common thing back then. Check the passenger side frame in the cab. There should be a 8 digit code. If the frame number and engine number are different, it’s not the original engine. I suspect that it might be the case because custom wood cabs were very popular when the TT first came into production but by the end of the run, almost every cab was made by Ford. Who knows, you may have a rare 27 custom body. Keep me updated on your findings! Congrats to Eleanor on her first TT.