Clutch cable: How tight?

I have a Steeda firewall adjuster and clutch quadrant coming today... How taut should the clutch cable be? Currently there is a good amount of slack... If I put slight pressure on the pedal, the pedal vibrations go away and the chirping (I assume TOB) sound also goes away.

How taut should it be? Can it be too tight?

The Steeda instructions say:

"The clutch should be adjusted so there is very little or no slack in the cable, and the cable is keeping constant light tension on the quadrant. If the cable is TOO LOOSE it may result in a vibrating clutch pedal or rattle under the dash. If the cable is TOO TIGHT damage to the clutch or cable may result. As the clutch wears, the cable will get tighter and the clutch will need to be readjusted."

So this theoretically WILL fix my clutch vibrations/rattle. Thanks to the StangNetters who advised so