A pair of Kadee Magne Matic uncouplers (#322) would do the trick.
Unfortunately I only had code 83 uncouplers and my track is code 100. So I had to shim the magnets to rise their height to were it needed to be.
Positioning the magnets is critical, because they need to be centered between the rails, for the uncoupling levers to work properly.
I used a contact cement to glue both the shims and the magnets to the ties.