As Timmy posts his questions on every possible forum, we already answered the question on Mylargescale.
https://www.mylargescale.com/threads/how-to-i-replace-the-amber-headlights-in-my-bachmann-heisler.95915/
https://www.mylargescale.com/threads/how-to-i-replace-the-amber-headlights-in-my-bachmann-heisler.95915/