I did a retrofit install in a 6 with a D-100. Great system! Your roll servo install will be more like Brian's, but our pitch servo installs will be similar. Brian is the man with Dynon gouge, but I'll help if able.
For refs, here's some links to Dynon's online info:
Overall Dynon AP info
here.
Detailed Dynon product documentation links
here.
RV-7 (-8 and -10 same) Roll Servo install info
here.
RV-7 (-6 and -9 same) Pitch Servo install info
here.
Good luck! The install process is not bad, though you will get into some contortions enroute, and get into some nooks and crannies running wires. Very doable though. I added the AP-74 and like it too, FWIW.
All very worth the effort...have fun!
Cheers,
Bob