I have recently bought an old Raymarine ST7002 SmartPilot controller very cheap, which I would like to use as the control for Pypilot, either because I like to have a nice control box for in the cockpit and certainly also because it makes for a nice hobby-project
 
I have working Arduino code running on an Arduino Mega incl. hardware to read and write to the SeaTalk-bus, so I can read all button presses on the ST7002 and am able to process them to PyPilot. 
What I want to get working now is sending identification, status, course and rudder data to the ST7002 from PyPilot so that I will show this data on the ST7002 screen.
I have a SeaTalk log from an SPX5 course computer (but without timing), so I can try to reverse-engineer that and see how often / when I have to send a certain SeaTalk message for the ST7002 to accept it as if there was a real Raymarine course computer on the SeaTalk bus. 
When this is working, I will also need to extend the serial communication between the PyPilot Pi and motor controller Arduino to include (at least) course information. But that will probably (hopefully?) not be the most difficult part.
I have searched the forum for quite some time, but, to my surprise, no-one seems to have done this, or at least has not posted about it here. Is there anyone who has tried or done this already?

However: Not a lot of people seem to be using Arduino's anymore to interface Seatalk from PyPilot since they use SignalK. That might be an option too, but will SignalK acually be able to act as a 'virtual Raymarine course computer' on the SeaTalk bus, so that the ST7002 recognises the virtual course computer and displays the data? Or are the necessary SeaTalk messages not included in the conversion, since they probably never have to be in a real Raymarine controlled SeaTalk bus system?

Regards,
Reinier