i would convert to hydraulic. its not hard and will be a huge improvement. when i researched my purchase a few years ago what i learned is that with cable steer there is slop in the system, so pilot tends to wander about. also in case of emergency maneuvers were needed, with hydraulic your still able to steer with the auto pilot on, however you can't overpower the cable steer without breaking it (if thats possible). not to mention the steering with the AP off is way better. i've got little to no torque steer now. no feedback to the wheel.
I’ve got a Raymarine S1000 setup (S1000, ST6000 Headunit, fluxgate compass, linear feedback, and a big accusteer HRP 16-12 pump if you’re interested. It’s Sea talk 1 so you would need to covert to NMEA standards with a cable.