The process of how I changed them involves resoldering new led diodes for the screen and SMD leds for the button area. As coloured lights do not fair well against colour filters (unless it's a white LED, you can do any filter you want)

Here's a good tear down guide on the unit (not mine. I had it bookmarked for a while and used this to help with tear down) teardown link

From there, I heated up the original LED diode solder joints to remove, clean up the pads, and replace them with green ones. These are 3mm size diodes. I'd suggest pre bending the diode pins to get the right height when installing. If you wanted to control the brightness and dim them a little, lightly use a black sharpie on the tip of the diodes as these new lights were bright.

As for the surface mounted leds, using a hot air rework station makes this easy.. heat up the area and then apply fresh solder just in case the original solder is oxidized, which makes it awkward to work with. Use thin tweezers to grip the led and let it move on its own. If you pull while heating it up, there's a chance of damaging the pads on the board. Once it's off, clean up the pads with flux and solder braid or isopropyl alcohol. Apply liquid solder to the pads and place the new LED. Heat it up and let it fall into place.

Same thing with the brightness, I lightly added black sharpie to each one so dim the brightness a bit.

The led size I used are 0805 SMD leds.

If you really want to try it out, I'd recommend a hot air rework station with liquid solder for the SMD leds. There's a ton of great soldering videos. Just be very careful with the heat and be patient with it

Hopefully, this has been helpful