BadJoey, Just to clarify, did this shifter use to perform well and for whatever reason, now it's not? Or, is this a problem that you are not well familar with and are trying to figure out where to start?
The reason why I ask is because I went through a similar situation. The problem ended up being a collection mis-matched parts from various B and E-body linkage operating levers, linkage rods, and shifter mechanism. Once we obtain the correct parts the car shifts perfectly.