My 74. Rear trunk .When I insert let, lock turns but will not release trunk when pushed in. There is a hole drilled under lock with rubber plug.

You can just barely access the rear trunk hinge bolts from the engine compartment and remove or loosen all 4 in a worst case scenario and lift the trunk from the rear.

Then with a long hooked wire and flashlight you can reach the latch to release it.

I did this once on a car I bought with missing keys and a locked rear trunk.

Not easy or fun and took a while but nothing was damaged in the end except for a couple knuckles.