I don't think there is a release any where?. I'm sure you have done this but get a can of WD-40, use the little straw adapter it has on it,and stick it in the lock and spray. You may have to start by spraying the outside first to get the little flap that closes the key hole up to loosen up. Start easing the key in,you may have to jab at it a little to free up the cylinder.Another thing, with the rear seat out if you take a flash light and a real long screw driver or maybe a tire iron with the chisel end on it,reach up to the lock mechanism and try to pry the clasp apart from inside.This just might work especially if you could get the key to go in. My key stuck in the lock in the open position and I had to take the lock mech. off because I couln't get the key out. If you had long enough tools you may be able to reach the screws that hold it together from inside.If you can you could then pry the lock off that way. I know thats not a tech type answer, but if need be think primative as to how to solve the problem. Good luck big guy.....Marshall