After you gain access to the center console section, you will need to reach forward of the gear lever area
as far as you can to get to this.

This is what locks your throttle cable in place.
Pinch the tabs together to unlock.
After removing the cable on each end, (pedal and engine) attach a wire or heavy string
to pull the old cable and SLOWLY pull out the old cable.
You will need to pull from the engine side to remove.
Attach the new cable to the wire/string and SLOWLY pull in the new cable.
Of course you will need to pull from the pedal side.
NOTE. The locking tabs only lock in one position.
I don't remember if the tabs are left to right or positioned top to bottom.
Just remember to take note on how it is locked in place before you unlock it.
Using a wire or heavy string will ensure that you route the cable correctly.
I hope you have a small hand to get to the locking tab as you will need it.

EDIT to say that this was on my 88 when it had the V6.
[This message has been edited by LT188GT (edited 10-18-2011).]