Sounds like it's just out of adjustment. A scantool that shows P/N switch such as Turbolink makes it much easier to adjust. You could just use some trial and error and probably get it right.
You can see the rod that goes to the steering column from under the hood. It's adjusted from under the car. Follow the rod down and you'll see a 13mm bolt. Just loosen and adjust 1/4" or so. If it doesn't help, go the other way.
You can also use your reverse switch to help (it's in there too) Just make sure your reverse lights are coming on when in reverse. Good Luck. You will like the chip when it's right.
p.s. Eric, I need a couple chips for a local build. Plus, I owe you some money for my WideBand update. Will get with you offline.