Excellent research from your side so far.
Correct, pin 3 in connector B on the RNS-E should get the GALA/speed signal1. The GALA signal has to go to what pin on the RSN-E ? (is it pin 3 V-signal connector B ?) In Radef's install it went to pin 1 on the "8 pin connector 3" plug, but then neither harness has this connector wired through (eg pin 1 connector 3 to the RSN-E pin 3 connector B)
Correct too.2. The K-line (pin 7 connector 3), should that go to the RNS-e pin 5 connector B ?
They should be the same except for the speed wire which would be missing in the A4 adapter. Moving the speaker connector over to the other adapter and removing the Bose wire should do the job.3. Are the harnesses the same for A4 and A6 installs so if I could correctly cable the Kufatec unit with speaker connections and remove the Bose link the it should work ?
The connector you are talking about is SMB (used on the older RNS-E and Symphony I). It will fit but it doesn't lock and may fall off eventually. But the antenna should work, I have seen two cars so far which had an SMB GPS antenna connected to the RNS-E and it was fine.4. The GPS does not have a Fakra connector, the brass plug it has seems like it will fit (tight), will this work ?