1980 Chevy Corvette, unknown mileage, unknown engine size

If your car is automatic. There is a cable that is attached to the the floor shifter. That allows the keys to be removed only when the car is in park. The cable has an adjustment on it. It the cable is not full up in the correct postion. The keys will not be released. You can access the cable buy removing the transmission trim inside the car on the passenger side. There will be 3 screw hidden in the carpet. One front, middle and then behind the seat. Remove the cover. And you will see the cable from the shifter to the colum. See if it needs adjustment or reattachement. The other option is the key release behind the ingintion is worn out. In that case you need to have the colum rebuit. But you will only need to buy what they call a theft repair kit from GM.