Ive had a look at the circuit from the instructables and it looks possiable ! being a complete noob with electronics means im not to sure about redesigning / changing the schematic. Im most worried about this comment " add a couple of buttons and a little software and the 'jog speed' " LoL with this being the worst bit "a little software " . This is why a game pad looked so good but im now working my way through Eagle CAD as ive always wanted to have ago at PCB making . Maybe il have ago at the pendant in my link as i got all the schematics and Hex file from the site , shame it didnt have a componet list to make it easy.