Glad I found this, as my truck is doing the exact same thing. Only difference is, I put my idle shims back in tonight (3 on each side). Set them up the same way, 3 clicks each side. Idle is good at around 900, but the slightest bump of the pedal will send it to 1400 and stay there.
I've been having this problem for a while now, trying 1 click, 2 clicks, 3 clicks and finally got a tip that I might need the idle shims back in. Not sure if I should try 2 clicks on each side or not.
The best it has ran is 1 soft and 1 hard click each side, but the power was pulled WAY back. Sorry to hijack your thread, but this is the closest thing I can find to my problem. '96 215 pump, 0 plate, stock other than that.