G'day guys. Just about to run some cables in to a 2000 VW golf. Does anyone know the easyest way to get the cables through the firewall? Is there a factory grommet to go through or am i better off making a new hole in the firewall? I had a quick look the otherday and followed the cables up the back of the engine before losing them to the depths of the unknown.... Not used to working with these small cars

Thanks in advance for your help.
McHarg