It's all modules which need to be configured, so add new steering wheel with voice buttons etc then you need modules for voice control and Rhee configuration changed in the bcm so it all talks to each other.
I need to download the diagrams to learn more about their relationships, I'll bet that the custom and mk8 will be similar as it will be cheaper for Ford to manufacture.
Martyn may know but until there is such demand then it's not something that ppl will invest time in researching in a hurry.
Besides that, anyone with clone ids may be struggling to connect to newer vans let alone retrofitting things
56 350 2.2 130ps mk7 with 2 side doors
65 290 2.2 125ps custom with 2 side doors
07 350 170ps
Ids v86 licence + v86.04 update + xprog
hereIds map
here