replacing trunk lock?

[240SX_89]

The previous owner locked his keys in the trunk and tried braking the lock and they succeeded but didnt open trunk so they used a crowbar. I fixed it so that the trunk stays shut but the problem is that I cant open it with the key or the button inside. I want to know if I can just replace the lock or do I have to buy a new trunk. Also how is the button inside the car connected to the trunk. The previous owner installed a wing with brake light and they messed up the wiring could they somehow messed with the trunk release button.