[AWBenson]

You can use a number of techniques, including a simple planar projection. These numbers are usually on a relatively flat surface. A planar project at a 90 degree angle would produce no distortions to a decal and the base color can be procedural without much effort involved.

Generally, texture mapping mechanical objects are usually fairly straight-forward because they usually don't require seemless texture unwraping. If the edges to a shading domain on the UV map doens't line up on an object with a standard, solid material then you cann't see a seem on the model anyway. This allows you to get away with "sloppy" UV-mapping. In a production environment, this is good form because you aren't spending alot of time doing something that isn't even noticable.