You'll have to remove the inner door panel and the screws that hold the lock assembly in place. This will give you enough slop that you can pull the entire handle out of the door and turn it 90˚ to disengage the lock cylinder's rod from the locking mechanism.

Definitely fiddly, but doable with some patience. Went through the same thing about 6 months ago in my SDL so I feel your pain. Ironically, I found it easier to get the handle out than to put it back in!