[Slam]

You can do this by removing the centre console so you can get to the cable but it's (very) much easier with the dash out. Are you sure the cable is attached to the valve properly? Usually I put the clip on with the valve at its furthest throw, then make sure it's got the right range of motion on the controls in the cabin. Unless the cable is actually kinked there's virtually nothing that can fail on it. Except having it rust, I guess.

The actual throw is deceptively short. Have an assistant work the slider in the cab whil you push/pull the end of the cable by the firewall. Check to make sure the clips are exactly where they need to be. If you do need to replace the cable, duct tape the new to the old and draw slowly through the firewall.