You'll need an electronics kit:  A search on "500UA VU Meter Warm Back Light Recording & Audio +Cable with Driver Module". Should find you one of several hundred that will work. The meters themselves are 35x35x37mm to help you narrow it down. Also included a pic of the PCB for reference.

Made this just for fun to see if I could. Turned out really well. Obviously the quality of your RCA jacks and wiring of the pass-thru for the meter can and will affect your sound. You should shoot for .5 Ohm or less measuring impedance from each channel IN to channel OUT. The TAP themselves are fine to use the cheap wire in the kit.

Some 3m screws/nuts and a 12v barrel jack. maybe a switch. your good to go. 

Quick BOM for some cheap parts on Amazon USA.
[https://www.amazon.com/dp/B0DRNSWY1W](https://www.amazon.com/dp/B0DRNSWY1W)
[https://www.amazon.com/dp/B0799LBFNY](https://www.amazon.com/dp/B0799LBFNY)
[https://www.amazon.com/dp/B094VDX371](https://www.amazon.com/dp/B094VDX371)
[https://www.amazon.com/dp/B07Y8MFCJD](https://www.amazon.com/dp/B07Y8MFCJD)

and if you want to dim the lights you need to remove the POT from the board and replace it with:
[https://www.amazon.com/dp/B0D6YHTQ8X](https://www.amazon.com/dp/B0D6YHTQ8X) or similar.