It looks like an '80s Ford medium-duty to me.

How well does it run? Better than the BLI trucks? Do you have to push down on it sometimes, to help it along, or does it run ok on its own?

This is the one I used:

http://www.thesource.ca/estore/product.aspx?language=en-CA&catalog=Online&category=Soldering+Tools&product=6412006

The included tip is the bottom one:
http://www.rpelectronics.com/jt-009.html

I couldn't do it without the solder touching adjacent pads.  Should I string the wires through the pads from the bottom, and then solder them?

I've got a 45-ton with the built in dcc decoder.

I've detached the onboard decoder, but how can I solder the wires from an aftermarket decoder, without the wires touching the adjacent pads? The pads are incredibly close together, as can be seen in the exploded parts diagram included with the loco:

http://www.bachmanntrains.com/home-usa/dwg/dwgs/85201.pdf

Should the wires simply be "strung" through the holes, and taped with Kapton, no solder used?