If put in the center of engine, the LED can be clearly seen, and it's not very nice.

Between two engines, it is much less viewable and lighting is more uniform as being indirect

same with the small central reactor.

Red center engine is a warm white LED behind a red transparent sheet (like on the real way).
In this case I have to change the box to position the LED below (and more uniform indirect lighting), and out of sight. So I had to remove the "floor" I originally installed.

Rather than a red LED, I use a warm white led. A red or clear transparent sheet painted clear red will adjust the right shade.

For the main reactors, I take cold white LED, which tend toward blue. If it is not blue enough, so I'll add a blue transparent sheet behind the honeycomb.

I found that it does not yet enlightened enough because the honeycomb grid limits the light diffusion. So I igh LEDs along the backbone, again to avoid direct lighting.
The box will remain removable, so I could still add even more later if necessary.