1994 Taurus shift problems, 3.8 engine

It started with the car rolling downhill, despite being in Park. We had the linkage adjusted, so that it would reliably go into Park, and lock the transmission. But now we have trouble getting it OUT of Park, and almost all the time it will not start when in Park, We have to move it to Neutral before the car will start. There is a considerable amount of play in the column shift position arc, such that when actually in Drive, it can look as though it is in quite a different gear, maybe two poisitions away. We have adjusted the wheel under the shifter, which controls the orange gear position indicator, but we still have a lot of problems getting it out of Park, and in starting the engine. Is there some other detent/lock mechanism operating here?