[Question] Locomotive Length

[Hack]

I've been tinkering with creating a new locomotive, but it appears too short. Coupling two units back to back causes the two to "mesh" without a visible seam between. Not only that, but running the two locos around has a herky-jerky look.

My question is: what variable determines the length of the locomotive?

FWIW, I have the set sitting at it's proper height above the rail, and everything else appears to be fine.

TIA.

[Hack]

Nevermind.

After selling the loco and re-buying, it sat properly on the rails. I guess some of the train data is saved with the save-game.