TAKE OUT THE BACK SEAT
You will have to remove the plastic panel from the door, which may entail removing the side plastic panels. Check for a youtube video.
You don't have a "Trunk" if you have an SUV!!! It is a tailgate or liftgate. You will need to be very flexible and get to the inside of the gate. Remove all the upholstry, any soundproofing or waterproofing and you can get to the latch.
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