I dont have a real jukebox, but have created arcade based jukebox software.
If you want to wire the buttons allready in place and use these buttons to been used, I recommend to use a keypad based jukebox software like Sk-Jukebox, DWJukebox as well MultiFE (my own software, using the Jukebox GUI and in vertical mode). They are all suited to been used the keylayout shown in the picture. MultiFE as well DWJukebox can both been used in monitorless mode.
Elsewise its same as wiring controls to a arcade machine using a keyboard encoder and connect that to a PC using USB or PS/2.
If you being using a touchscreen, you can looking software like Uncle'T Jukebox which can both to been used with touchscreen and keypad. There is other software of course, but not sure how they can use Keypad (such as Etouch and simular software) too.... But of course you can change these keys to been use for speciel controls as skip songs, pause etc and then change the labels.