1998 A3 Firewall hole?

[WillThePlank]

So about 6 days ago I picked up my new car which is an 1998 A3 Se 1.8.

The car itself is flipping amazing but I'm having trouble wiring in my audio gear. when I got the A3 the original radio didn't work at all. I got the new head unit in to find only the front speakers work (half amplified rear system) so I have taken the gear out of my old car ( 4 channel 2600 watt amp and 12 inch 360 watt tube sub ) and I have gone and got my new speakers and the mounts required to mount them in the door cards etc.

The problem I have is I can't for the life of me find a hole in the firewall to get the two power leads from the battery into the cab.

I think I might have found something which is a rubber gromit next to the air filter but I'm not sure if that leads into the cab yet as when I found it I had 10 mins before I left the area for a few days and I won't be back with my car tell Thursday and the pondering over where it went is going to drive me mad :P.

So does anyone know if 1 that is a hole that leads to the cab or 2 where one that does and I can easily reach is located.

Thanks Will.