help - how do I get cabling from my head unit to the boot?

[hejira]

I have a Series 2 NB, with an aftermarket alpine head unit installed.
I also have an amp & a sub I'm yet to install sitting around.

I need to run the cabling from the head unit, back to the boot where the amp and sub will live.
I can connect the amp to the battery fine, but how do I run the cabling from the head unit/interior into the boot?? is there a hole in between the interior and the boot or do I need to make one?

thanks for your help!

[Jeo]

Two large holes already there, one down each side of the boot. Have a look from the inside of you boot at the very back on either side or under the carpet on the parcel shelf and you'll figure it out fairly quickly.

[hejira]

great! thank you.