Hi Dave, in this scale I sometimes used fine stretched sprue for antenna wires, clear sprue being better to get the 'stretch' right, but I mainly use 'invisible' mending thread. This is available in clear, and a couple of 'smoked' shades, and is ideal. It can be painted if required, using the edge of a paint brush, and is easy to fix with a spot of CA glue.
This 200 metre reel only cost £1, and should be available from any sewing materials outlet, haberdashery or similar.