any ideas on which injectors? 4.2FSI

Hi all,
Im having a misfire in cylinder 8 along with all the wonderful lights that go with it. No fault codes when plugged in though...only reason we know it is cylinder 8 is that when coil pack and plugs were removed plug 8 was dripping fuel and the coil pack was almost dusty (whats that about?), we then switched on the ignition for the fuel pump to prime and noticed when looking down the hole that clearly that injector was stuck open as there was a constant flow of fuel. we are looking at tearing down and replacing but I can not find what injectors we need anywhere!!
wondering if anyone knows in here?
Aiming to manually clean the carbon build up the best we can whilst its apart too, im sure that's going to be fun.
if anybody can point me in the direction of any parts that will need to be replaced when stripping down that would be ideal (seals and clips that may break/perish)
Thanks in advance,
Dep.