Don't adjust ANY of this with throttle cable tension. The throttle cable should be completely slack when in the rest position. You're affecting both the butterfly position AND the Throttle Switch position when you do this. There are seperate, proper, and necessary adjustment points for both of these.

The Throttle Stop Adjustment Screw, to keep the Butterfly from binding in the Intake Manifold, and the Throttle Switch Mounting screws.

The best thing is to get and follow the '71 E Shop Manual instructions, in proper order. Otherwise, unless you look very, very closely, and succesfully figure out the entire system, as it was made to work and be adjusted, you'll just be chasing your tail.

gary - '72 ES, '67 122S