Re: SSB Antenna wire
Use GTO-15 wire between the tuner and the backstay. This is high-tension, single conductor wire....essentially neon light wire.
At the backstay, one good and easy way is to use stainless steel wire clamps....the U-shaped ones with two nuts on them. Get a third nut (most are metric sizes these days) and fit a good ring terminal on the end of the GTO-15 wire to slip over one of the clamp studs, and secure it with the extra nut. This makes a very strong connection which can be easily removed, inspected, cleaned, or replaced.