Wheels and the Oil Tanker

I realized today I made a mistake on the wheels of the CS passenger. When I started a new file, using the wheels and basic lines as a template, I saw the distance between the inner "rails" to be NOT 4' 8.5".

These guys make and repair wheels axles trucks etc.
http://www.lyonsind.com/index.html

These guys make rail tank cars. They have diagrams in pdf form.
http://www.americanrailcar.com/RailcarManufacturing/Car.aspx?car=tank

http://www.railpark.org/stories/tank_car_cn_agrx-802.html


Lest I forget.
Getting the dome ends on the oil tanker turned out to be a major pain....
Eventually I solved it by using NURBS spheres in blender, creating circles and importing them into blender, whereupon I used RAW NUMBERS, not snap points, to solve it.

I don't like the 12'7" height the drawing asks for....

Not sure.