Interconnecting old and new instruments--a few questions

Thanks for approving my registration!

I have a 32 foot sailboat with the following configuration:

Autopilot:
Type 100 course computer down below
ST6000+ instrument at pedestal pod
Type 1 belowdeck Linear Drive
This system continues to work quite well and would like to keep it.

Instrument
ST60+ Tridata at pedestal pod
-Depth transducer directly connected
-Speed/temp transducer directly connected

New Non-Raymarine chart plotter/Radar with NMEA 2000 as well as NMEA 0183 capability at the steering pedestal.

Right now the St6000+ is interconnected with the ST60+ Tridata via a ST1 cable at the pedestal. The only real interfunctionality this appears to provide is power and the ability to control backlighting together.

I would like to feed the depth and speed data from the ST60/ST1 device to the chart plotter.

I would also like the GPS chart plotter to be able to provide steer-to-waypoint instructions to the pilot on occasion.

I purchased an ST1 to STng converter with an STng to NMEA 2000 cable and have not installed it yet.

I've searched and read lots of posts on this forum and am still not quite sure what connections to make. In general, what are your best cabling recommendations for the pilot and instrument?


Specific Questions:

1) My NMEA 2000 backbone has 12V power injected at the midpoint. When connecting the ST1 to STng converter, and then connecting the STng to NMEA cable to the NMEA backbone via T connector, do I need to also install the STng power cable, or is that redundant to the NMEA power?

2) Do I need to modify the ST1 device power wire as well? I have read here that one may need to clip the power lead in the ST1 cables in these situations.

3) Finally, if I need to use NMEA 0183 to connect autopilot to chart plotter, can I use the NMEA 0183 terminals on the back of the ST6000+ or would I need to run a wire to the course computer down below?

Thanks!!

Bill