I'm sure this has been covered before, but I couldn't find a link when I did a search.
I'm trying to set up my Logitech Rumblepads for Genesis games (among others).  The Logitech pads only drawback from what I've seen is that they only have 4 buttons on the right whereas Genesis needs 3 or 6.  I'm just curious if anyone can recommend a good layout?  The controller has 4 shoulder buttons, so it's not lacking in the number of buttons, it's just not in the original location.
I'm currently experimenting with ABC on the lower 3 buttons of the diamond and XYZ on 3 of the 4 shoulder buttons.  Any other suggestions?
I don't think this is as much of an issue for other consoles as I think Sega was the only one to use so many buttons on the right (well, I'm ignoring the Atari Jaguar cause it's a freak anyway  

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