This is from another board discussing using locomotives to supply power. The engine was driven down a street without rails. Once the engine is off the tracks, how do you get it anywhere but straight?
http://www.canoe.ca/CNEWSIceStorm/jan14_nphoto8.html
http://www.trainweb.org/canadianrailways/CanadaCalling/March1998.html
No, under no circumstances can a locomotive be steered. Of course, the photo and caption leave a lot of unanswered questions, but I am led to believe that when they say “driven” down the street, thet mean transported on temporary rails, or by crain, or perhaps on streetcar’s existing rail.
A locomotive also masses so much that it surely would sink into the pavement of the street if it rested thereon, with nothing under the wheels.
Curses! I meant to say “Crane” not crain…
Man, am I tired…
You don’t - the locomotive will continue in whatever tangent line it was following (subject to vagarities of the ground - i.e. slope toward the gutter), meanwhile carving grooves out of the asphalt.
I suppose you could pull the forward truck (wheelset) with chains from side to side to guide the locomotive a little.
Man, I forgot about this, although it was in all the railfan press at the time.
Actually, the answer was in the news report you supplied:
“The locomotive was lifted off of the tracks by a crane, and placed on de Montarville Street, and allowed to proceed 1000 feet down the street under its own power. The locomotive initially rolled on the edge of the wheel flanges on top of the pavement; the weight of the locomotive eventually cut flange-deep grooves into the asphalt of the street, this locomotives was used to generate electricity for the various local municipal buildings.”
Here, I’m assuming straight line.
I should read these things more carefully.
To steer a locomotive you need to remove its nuts.
Sorry, I couldn’t resist.
Wow. I tell you what, wow.
I thought I was going to be a smart ass and post a silly answer, but my little They Might Be Giants lyric pales in comparison to the utter weirdness of your post. My hat is off to you, MC. You will always be stranger than I. 
Well, since I went to all the trouble of waiting for the message board to let me post a response, I’ll put it here anyway:
Now I’m gonna go eat marshmallows and sulk.
I recall reading the referenced story in the railfan press some time ago. It was possible to run the locomotive several hundred yards down the street mainly because a) the trucks (wheelsets) were aligned stright ahead to begin with, b) the locomotive was operated at extremely low speed c) the wheel flanges cut into the roadway, which was of consistent hardness.
Beyond that, one can ‘steer’ a locomotive by placing wood blocks alongside the wheels to guide them one direction or another in small increments. This is often how minor derailments are resolved.
Kids, don’t try this at home.