Why not just make the panel at the top of the calc( that way you dont have to reach over other controls when you want to play games) and put the EII port on the top side, more like a game boy cartrage?
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/
__ \
| custom / \
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| buttons | S |
| that badly typed oval thing is the speaker :D
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\___/ |
| ______________ |
___calc top_____
/ calc screen
\
/_______________\
| +
|
|
EII slot |
| rest O' calc
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