Vectran steering cables

[Asylum]

Wheel steering on my 38 foot racer is via a short chain on sprocket on the wheel - the chain then connects to two vectran cables that run through turning blocks and back to the rudder post quadrant. The chain connects to the vectran by spectra lashings. The lashings have to be adjusted to account for stretch fairly frequently. The kind of boat that I have (Sydney 38) has had a number of failures of this system. Some of the failures have been caused by the vectran cables rubbing / chafing on each other and eventually parting. They touch where they criss-cross on the way to the quadrant. Other failures have been from breakage of the lashings.

I'd like to make two changes:
1) I'd like to put some kind of thin jacket over the vectran where they can rub and chafe. The jacket may make the rubbing slightly worse but would be intended to protect the vectran "core".

Any opinions about this 'fix' would be appreciated.

2) I'd like to replace the lashings with some small stainless or bronze turnbuckles - both to minimize the chance of failure and to make it easier to adjust the steering. Again - any thoughts on whether this is a good idea are welcome.

The last thing that I may be able to do is to slightly move (raise) one of the turning blocks that the vectran runs over to provide a bit of clearance between the two cables at the crossover.