Neo-Geo Forums

Hi,
I am still trying to build my supergun so I can play my MVS one slot. Does anyone know how to build one of these. I do know where to buy one but I would like to build one.
I was told BWI built one. Any info?
I do have this site: http://www.mit.edu/afs/athena.mit.edu/user/c/w/cwu/www/work/
But he has not told me how he built his.