when ford has the same color and wire stripe configuration used and this conductor hits a splice.... the downstream conductors after the splice have skinny strips.
example...
front lights are fed with a brn white conductor.
There are several brn / wt branches off this main feeder which head out to the front left and right side of your car.
these "secondary" branches are bn/wht yet the white stripes on the secondary branches are very skinnny.
the main feeder brn/wht has thicker white stripes.
thought i would share,, there seems to be a logical pattern.