E30 Zone

I've read about this on lots of posts before but I can't get to the bottom of my issue
Ive got a cabby which deadlocked itself. We have manged to free up all the locks bar the boot (think the deadlocked fried the motor)
Can hear the motor locking in boot but not unlocking when we do the 12v onto blue/white wire trick.
Sounds like we'll have to break in and I read I can drill a small 2-3 mm hole to do so which will prevent damage. I don't want to smash light, etc
Can you possibly let me know wjhere to drill. Ive taken the plate off but dont want to make a mess
I know people have security issues with this info but I don't think I have a choice. Happy to provide proof of ownership if it helps
Thanks

Can anyone help with this please, getting desperate

Back up, can anyone help, I've tried something else today but still no joy
Don't really want to break a rear light if I can avoid it

.. dont break a light ,there £40 to replace !, im sure s'one will respond soon

Thanks Will, the key turns the lock fine to both the horizontal and vertical axis. However, the button doesn't do anything
I'll try the steps you've said, but I thought that if the key turned, there's no reason that the button wont unlock it but its all new to me, so I may be totally off topic
What I can say is when the ECU died, it fried all the motors as we've had to put new ones in the doors, so I'm guessing the boot is similarly fried. I just don't get why you shouldn't be able to manually unlocking it using the key and boot switch.. especially since there's no deadlock as you said
Fingers crossed, your idea works .. thanks for your help