Thanks modded, I will have another look this weekend.
I'd also appreciate some advice on the following:
I want to install rear speakers, but for reasons beyond my male comprehension, my girlfriend doesn't want them in the parcel shelf. As she's the main driver, I'll reluctantly go along ...
However, I don't want to waste space by placing boxed speakers on the boot floor, so I've been thinking about cutting some mdf to fit the green shaded area and install the speaker(s) in there. Would be a perfect way to utilize otherwise wasted space.

http://img148.imageshack.us/img148/7821/trunkb.png
The easiest way would be to just leave the bottom open, but I'm curious how this will affect sound quality. Actually, I'm curious about whether this will work at all! Anybody got an idea?