Have a look at this page (21-19), (Fig 38) from the FSM, and step (3) "Slide tool C-3951 over the levers, Inserting center pin through the first two levers (Fig 38). Tighten set screw securely. (this aligns the 3 levers in the gear shift control assembly, and holds them in neutral position)".
So, the book says 3 levers, but I find it confusing as to how it actually works. Notice the special tool slid under the shifter. What makes it even more confusing is that this is a B body illustration, no A body illustration shown. A body has the taller shift stub and a hole at the bottom of the shifter this one does not have.