That's a pretty significant crack. I wonder what caused it.

There's a surprising lack of rust on the front of the Corsa too.

I completely removed the aircon from my old Corsa by doing exactly as you mentioned, however it was a 1998 model so possibly less complex than yours.

You could pull up the back seat just to check the top of the tank too. It's pretty easy to get to.

With regards to the heater console lights,...

You might just get away with it if you grind back the nuts holding the arch trims on.

I got mine off eBay and it was perfect for the job.

I considered it a few years back when I had a bit of spare cash. Wouldn't mind doing it at some point in life.

End of the fucking world is well worth watching.