727 kicking down too early

That could have been it, try re adjusting your kickdown cable. Sounds like something changed there like the kick down cable is not returning, especially if you have it fastened to the body somewhere creating a pinch point.

Here is a picture of a factory kickdown linkage. If the Green return spring was missing it would act the same way your's is acting.

Want to make sure that slider arm is all the way forward at an idle, and not a gap there with like the kickdown linkage/rod/cable pushed back already.Edelbrock Mopar.jpg