Grasshopper, you have a classic Samurai problem called the disintegrated shifter sheet!
The cure is to replace the shifter sheet which - fortunately - costs from 10 to 20 bucks!
Do a search for shifter sheet at Ack's FAQ (the link is in my signature, below) to find out how to fix it and where you can get a replacement shifter sheet.
I don't know of a single Samurai owner (myself included) who hasn't replaced their shifter sheet at least once...
FYI, I would go with the Zuks Offroad (ZOR) brass shifter sheet. It lasts forever!
I hope that this helps!