Can anybody assist? The current position of my back-stay insolater is at above head height which means that I need to keep the SSB cable away from the stay by the use of plastic tubes. I understand the burns risk when transmitting.
However would it not be easier to have the insolater at the bottom of the stay attached to the hydraulic ram, with a tube on the stay above the insolater for burn protection?
Better opportunity for maintenance, less joints in the rigging, less cost.
Any experiences or thoughts.

I am not a radio expert, but I have spent a lot of time looking at the isolaters and the antenna wire running up to them. They always are located about 4-6 feet above the deck, and no there does not really seem to be much sense in this, particularly when you consider that the antenna wire is in fact part of the antenna and not as some think a lead to the antenna. However, I am not sure how good it would be for the hydraulic ram to be subjected to 5kV, particularly since it is also presumably connected to your hydraulic pump etc.

As to the burns risk, I am sure you could add a tube to the antenna wire leading to your back stay. However, our experience is that when we use our SSB we are both there listening intently - the evening 's entertainment.

What is very important are the spacer tubes you mention. the antenna wire must be kept well away (4 inches) from any parallel metal (back stay).

Bottom line, changing from what you have would be costly, so why do it?