I would certainly file a claim with Mr. Fedex!.  Hope you saved all the wrappings, packaging, etc.

Learning to weather with an airbrush is an idea--I use "earth" and other dirty colors sprayed upward at the bottom of a car to simulate the dust and gunk that gets splashed up by the wheels.  Also streaks on the ends in line with the wheels.  Take a look at a real car--what manages to fall on the upper parts will be washed downward by rain. Ground chalks and weathering powderl like Bragdon's can be washed off if you don't like the results.  gj

You are running afoul of the Laws of Physics.  No--the Physics Cops won't be there, they just send out gremlins to keep the power from all getting to the trains.

Seriously, most phone wire I have seen is about 24 gauge, bell wire about 20-22 ga. A Water analogy is often used with electricity.  You can only put a certain amount of water through a hose of a given diameter. Likewise, you can only get a certain amount of electricity thru a given size wire.If you have any significant run of track, or are running more than one loco, you should be using a minimum of 18 gauge wire.  Or--run bus wires of 12 ga building wire under the layout, and use the phone wire for feeders (not more than 6") to the track every 3-4 ft.

gj

Just be certain that only one throttle can be connected to a given section  of the track at a time.  The voltages can be additive-- (2 12-volt supplies put 24 volts on the track. Or--if one reverses, has the potential of producing smoke and electrical damage.

I know the cars you refer to--have a couple lettered F&C with the transfers that used to be available--the ones at Durango are definitely bigger--includes the hopper you refer to.  gj

definitely nice-looking cars.  I saw samples at Durango.

The samples I saw at Durango are definitely 1:20.3 scale.  There was an older small car, also supposedly 1:20.3, but matched some of the earliest Rio Grande cars. gj