I'm pretty sure of what you just wrote but some people might mis-read it.
The Neutral indicator light can be swapped out with a LED without a problem.
The turn signal indicator light can be a problem unless the correct type of LED is installed.
For this turn signal indicator light it must be the kind that will work with the electrical polarity going either way. (+ can be connected to either light contact and it will still work).
Most LED's will only work if the electrical polarity is only going one way. (if the + connection is hooked to the wrong connector the bulb will not light).