You could place this is in illustrator, and define a bruish from an image of the scale. Then apply it this scale brush to a vector path tracing your winding road. Keep the stroke weight at 1 point, but not sure that would be 100% accurate though.
A simple method that would work 100% is putting a string up to monitor and curve it along the road, then mark the endpoint on the string with a pen. You only then need to straighten out the string and place it along the scale.