Tip for fishing cables through wings and fuselages - buy a long length of 'bath plug' chain, the sort which has loads of tiny spherical balls along its length, tie a thin piece of strong nylon cord to the end to act as a draw line.

The bath chain is heavy enough to allow you to feed it through the most intricate internals, the balls help to prevent snagging and it has saved me hours over the years trying to find routes through wings etc

You mention Ashlok connectors which I know are hard to find as the guy selling them decided to quit, they are made by Molex and sure if someone planned to they could source and sell them - just need a UK model company to do the leg work.......

marcs