Stripped it down today and found that the cast actuator on the back of the lock barrel has broken up.
If anyone has a hatch lock barrel for sale, please let me know. My car is an '87, so it doesn't have the microswitch on the back of it like the '88 onward cars did. Not sure if the mech is the same other than not having a microswitch, but a photo will make it clear
If you can help, please let me know.