I'm not done with the tut. Personally I'd like more BNSF wellcars too so I'll see it through. Disclaimer; it's not prototypical, not without shifting the ARN anyway, and I am by no stretch of any imagination a competent reskinner - there are much more talented folks around here.
Long story short you'll need either the source files to move the numbers (they're part of the mesh, offset by about 5mm) or create your own ARN mesh (just simple planes to stick the digits onto) and use the config to add it as an attachment. Alot of work, something I've never done before.
Huh word it better please because I'm not that good at messing with configuration files and stuff would they look good with the default arn attached? So I won't have to move it around could I take jointedrail's single bnsf h3 well car configuration file and replace the ttx file so the Arnold is in place? If not just a thought.
Yes, that's what we're doing, creating our reskins around the existing ARN. Your results will look good - if not 100% proto - so long as nothing is overlapping the digits. (Looking back now I realize I made a glaring mistake, will fix.)