[rfeenstra]

I haven't had much problem with the wires coming loose. They are usually wrapped around the terminal several times. I would try to solder the wire to the part that is protruding that is within your drawn circle. Any connections to the top of the terminal can then be soldered quickly so the heat does not have time to transfer all the way down to the coil wire. Secure the wire on the surface with some sort of adhesive.