Re: Gradient Ramp not showing in viewport
It's possible that there aren't any UVs on your cable, which would explain why it still looks solid-shaded after the material has been applied.
Try selecting the cable, and go to the Modify Panel. Under the curve's 'Rendering' roll-out, look for the "Generate Mapping Coords" checkbox, and make sure it's enabled.
This should generate UVs along the cable geometry, and allow your textures to become visible on the cable's surface.
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