Hi, I did an experimental move on this scenario but the game didn't like it so I thought I'd suggest it here. Basically you'd the same thing as before but have to do an extra step. You have to couple the helper engine to the rear of the train so you have 1 at the front and one at the back. for the last leg of the journey while you are at the Tees Engineering Yard leaving with a more uniform consist. I quite liked the looks of it all.