Yeah - im making a bartop with one of those namco units too. Its a pritty easy hack. But your right though, the stock stick that it comes with is pritty flimsy and deffently need replacing. You also need a power pack that give a 6V output, at around 500ma (thats what I used anyway with no prob's).
Not sure if you need the LED in there for it to work, but I kept it in there, just so its all still drawing and using the same amount of current as the origonal.
Hope this helps. Let me know if you need some help with plans for the box, ive got some here on paper, but I could scan them in for you.