I am fitting a second battery and want to put a new cable from a control box by the original battery to the new battery at the rear of the car. I have had a quick look and can't see an easily accessible way through the bulkhead.
Has anybody found a way through?

Also, I will need a switched 12v supply from the ignition - is there a good place to get that too?

switched 12v in passenger footwell At work
At home

"I can't always believe facts I read on the web" - Charles Dickens

winner by default of the tractor vs caravan race

Theres a 12volt feed in the boot (the one for the caravan feed)
its works when you put the fuse in and its ignition feed. no good if your already using the caravan feeds, and you will need to modify the wiring slightly. its the one which is used to charge the van battery. may be of help ??

Not sure if this will help but I ran a 1/0 gauge through the drivers side (left hand drive) just behind where the battery is under the hood. take the battery out and there is an existing rubber grommet its about 2"x3" almost square. i just popped out the grommet drilled a hole in it and replaced it.