Bone stock - need advice on upgrades!

Hello everybody.

I recently purchased my fourth Skoda, my third Mk2 Octavia. It's a 2005 1.9 tdi hatch that I got at a really good price. Apart from a DSG and front fogs it's a very standard thing so there are quite a few things I'd like to upgrade, which I'd like to ask your advice and opinions on.

1) I -want- a jumbo box. There is just something about it that makes me feel the car is a lot more car somehow. I'm having trouble sourcing what I need, there don't seem to be a lot of them on ebay? Do you think a UK scrapyard would send me what I need if I contact them or are these things just rare?

2) It only has electric windows in the front, how much of a hazzle would it be to retrofit them in the rear?

3) Tune - it's done 240.000 km (about 150k miles), but being a turbo I'm thinking it can be boosted a bit more? How complicated is getting it tuned (or doing it myself if possible) and is it likely to damage the DSG?

4) Audio upgrades - I've got the stream and would like something a little more fancy, preferably with active aux and bluetooth, android enabled touchscreen wouldn't be bad. What have you guys been doing on this front, how important is it to stay with a Skoda unit vs. aftermarket?

I'll throw in some pictures later if you're interested, but it's still just basically a stock white Mk2. That will change though, and when it does I'll do a before and after thread!

Bye for now,

JJ