the 25-600 is the right (weaker) coil. The wiring for putting a resistor in to further reduce the power is (I hope!) attached - I would recommend it on Meteor to save damaging targets on the large bank. The chattering could be two things. The outer switch on the bottom not making good contact, or the hold wiring (thin wire) on the upper flipper coil is broken (or even a cold solder joint at the tab).
Hope this helps...
