Will a throttle cable stretch over time?

67Dart-
We are clear of the carpet, and when the cable is adjusted all the way back in the bracket, I obtain WOT, but that is when the internals won't close and leaves me with high idle.
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Just a thought. When you adjust the cable "conduit" back (in post #6) are you holding the throttle in the closed position? If not you need to. Then move the cable "conduit" forward .060" and tighten the nut. From there manually open the throttle and make sure it opens completely without bottoming out anywhere on the cable.