you need to haave your desighns ready depending on what shape you are trying to make i went with a standed stand up cab. you can getmy plains at my site here http://coolprojectsathome.webs.com/.
Step 2: Wiring it all up
you need to hook up the video to your Raspberry Pi to you tv/monter and the sound. next you can start hooking up you I-Pac 2, this is a simple wiring diagram for the I-Pac2. All of your buttons and joysticks will be wired the same way.
Step 3: Getting the games
now you will need your games you need to first get PiMAME you can get it by serching pimame on GOOGLE. now the games i cant tell you where to get them because of legal reasons but i might susgest that you mybe type in to GOOGLE PiMAME roms.
Step 4: Finished
now you are finished all you have to do is get your settings right and everything will go good if you build this post some replys to me please.