Wish I'd seen this post before letting the other half loose on ebay, as got a head unit from a T6 on the way to me.
Anybody know if the dealers will code the unit to the van?????
Some people have had dealers remove component protection for them so it can be done but lots are reluctant to do so. You might need to prove the unit is not stolen and so on. You probably can't do this with an ebay item?
The biggest hurdle you're going to have is the compatibility aspect mentioned above - if the T5.1 modules don't support the coding required, it won't happen. Even if they do, are the modules even compatible with the newer systems?
The T5.1 modules/CAN is roughly speaking equivalent to Golf Mk6, the T6 uses the same system as the Golf Mk7.
It's worth pointing out that in the Mk 7 Golf, if you didn't spec navigation when the car was built it cannot be added later. The VW factory refuse to do it. Even if you bought all of the hardware and coded it, the nav does not work. There are other options like the Kenwood add on and there are a few hacky things to get it sort of working but no way to give the same outcome as factory nav.
They certainly know what they're doing with this stuff now....