Note: This design isn't mine, it belongs to Caster / myfordboy (YouTube Channel) "Swing up LED bar for Creality CR-10 printer" was only designed for Creality CR-10, it was upload in Thingiverse on August 20, 2017. 227 days later, he decided to update and added two new things that it will work with Ender 3 and Ender 3 Pro too. However, he doesn't have Ender 3 to test it. I did print the thing made from Caster, its perfect match with x-axis mount but the screw isn't long enough to hold the mount and z-axis stepper motor too. So, I contacted him if he could resolve the issue, he responds, he doesn't have Ender 3 to test it. Then I asked him if I could modify his things, he approved. So this thing only designed for Ender 3 and Ender 3 Pro without replacing the screws.

You could use Caster / myfordboy's design if you also want to replace the screws too.

Warning: Do not overtighten the screws, otherwise the base may fall. Make sure check the stepper motor and x-axis mount that aren't loose.

If you want to see the video for how-to assembly the Swing up LED bar: https://www.youtube.com/watch?v=R-kSlTfZ6Ng

The description below is copied from Caster's original thing:

• The light bar gives light just where it's needed and can be swung out of the way if access is needed to print head. It gives good illumination to the bed for taking photos or videos.
  The LED strip is very cheap, this is the link 5m LED strip
  https://goo.gl/SqTKfn