New 3D Engine Shell

I assumed that they modeled it after the DE-10 in which case the long nose would have been the front

Looking again at the original lister's page it didn't actually say what model it was meant to be, but looking at the cab it looks like it can operate in both directions and in the illustration shown on their page the connector is indeed at the 'long nose' end.  Maybe that was just convenience though as if you had the shell the other way round the switch would be in a very awkward place and probably need some form of extension to make it accessible to turn it on/off (I had a similar issue with another shell I was working on and did go for the switch extension idea)...