Help with fitting speaker wiring from HU to parcel shelf

Hi all,

I'm tempted to get some speakers in my parcel shelf, although I dont have any speaker wiring going to the parcel shelf as there are no speakers there in the first place.

My question is, how easy is it to put wires from the head unit underneath all the carpets I presume into the boot/parcel shelf, and does anyone have any pictures of having done this?

any comments appreciated, thanks!

P.S. I'm not very good with things like this.