Adjusting Three Peice Kickdown Linkage

Here is your base line for the kickdown adjustment. Get it so that when the gas pedal is on the floor, the lever at the transmission is all the way back. That's your starting point. If it holds the shift out too long, then you shorten it up some.

That said, the kickdown is not going to make the transmission act like it's in neutral. You have other transmission issues, I suspect.