From the source data in the photo I'd say the loco is an ex Southern Pacific GS-6. http://en.wikipedia.org/wiki/Southern_Pacific_class_GS-6
Smoke deflectors were common in the UK to lift the smoke clear of the cab. The only railway that never used them was the Great Western Railway were the excellent aerodynamic design meant that they weren't needed.

You can watch The Railrodder on the National Film Board of Canada's Youtube page. No, that isn't a spelling mistake. The title is Railrodder, not Railroader. I have no idea why.
What would have happened if the ad in the newspaper had been Drink Canada Dry instead of See Canada Now, I wonder?

I concur with the honourable gentleman. Remember the golden rule. If you can see the oil, you've used too much.

When you get everything working again, fit a Double Pole Double Throw Switch between the outlets of the DC and DCC power feeds.

There are four sizes that I know of. 1:160 which is used in the US, Europe, Japan and other countries.
1:152, which is the old Treble-O used in Britain.
1:150 which is another scale Japan uses.
1:148 which is British N scale.

The Bachmann 36-558 decoder cannot be used on DC as Bit 2 of CV29 is not supported on this decoder.
Only CVs 1, 7 and 8 are mandatory according to the NMRA Recommended Practices.

You might get some answers on a UK forum, such as the New Railway Modellers forum.

It's a little more complicated than that, depending on who made the decoder. The Loy's Toys website explains the difference between  "Automatic Analog Conversion" on decoders and "Dual Mode" decoders.
http://www.loystoys.com/info/analog-conversion.html

Marklin tried them in 2007. They seem to have been a failure because of poor running under DC.

The 'ready' in DCC Ready means it's ready to have it's light board removed and then replaced with a DCC Decoder board. Until that's done, it's just a DC loco.
In some British locos there may be a socket or solder points for a DCC decoder to be fitted.

Was the loco described as DCC Ready or DCC On Board?

The UK Model Shop Directory has a list of specialist DCC suppliers in the UK if you're looking for a DCC controller.
http://www.ukmodelshops.co.uk/retailers/typeDCC-DCC_Specialists

If you're just buying the loco it will work fine on a UK bought DCC system. The UK uses the same NMRA DCC decoders as the USA. It will work with the Dynamis for instance. If you want to take full advantage of the sound functions then stay away from the basic DCC controllers and avoid the Select as it is not NMRA compliant.
If you are buying the loco direct from the USA remember that you will probably be charged 20% import VAT and up to £16.00 postal administration fee.

DCC Ready means it doesn't have a decoder. It's a standard DC powered locomotive that is ready to be converted to DCC by buying and fitting a decoder.

There's a handy 'tick box' CV29 calculator here. http://www.2mm.org.uk/articles/cv29%20calculator.htm
Also does CV17/18.