Your pics are great - I will upgrading my dash soon and good to see how you did yours.
As for the rear heater lines - I have a few gone on mine. I have done repairs before with varying success, but that was on a car where it looked like someone had regularly wiped the rear window whilst wearing rings or something - I would repair one break only to find that line had loads more
This video from the US is a good guide.
https://www.youtube.com/watch?v=r9NQ46ckgYw