Reply to 2 EUR controller

I was searching on instructables.com to see if they had any neat ideas for MIDI controllers and I stumbled upon this (it's not MIDI but I can see how it could work for me).

http://www.instructables.com/id/Easy...cal-Interface/

They basically ripped out the heart from a USB PC keyboard and remapped the keys they needed to new buttons. I'm using Serato Scratch with a Rane 57sl. I wanted to have an additional controller for cues and loops, so I can dedicate the controls on my mixer for effects.

Anyway, I went to the local Oxfam and bought an old Packard Bell USB keyboard for 2 EUR. Then I ripped out all the keys I don't need and put stickers on the remaining ones to easily recognize what is what.

I'm really happy with how it works but it looks super crap!

The next stage is to put this in a new housing and get my hands on some sweet buttons to replace the keys. Obviously, arcade buttons i the way to go on this

I've sourced the buttons and box but I wonder if anyone has any tips for hooking them up to the brains of the USB keyboard? Seems it's just a case of tracing the circuit back for each key - I'm hoping I can apply multi-key presses to one button.

Obviously, I'm not having nice things like knobs and sliders as it ain't MIDI but you can't beat the price!