Almost sounds like a vac leak to me, have you tries a can of ether under the hood while the car is running with the engine cover off lightly spraying ether around the vac lines (keeping the ether away from the intake? If you have a vac leak the idle will jump when it sucks the ether in, you'll have one leak at that area. Fix that one and test more until you can lightly spray ether and have no more idle jumping (remember to keep it away from the intake or you'll have false positives). Just a thought!