This is my aftermarket headunit instalation. In my head at the moment

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Instead of the old volume button - a hole pocket for eg. a pen...
It is an Alpine DVD unit, the plan is to get a steering wheel control interface, hacking to the LCD, Alpine bluetooth system, relocatind OEM HU. Any known solutions to the steering buttons? I believe that americans have a solution from PAC and I think the steering wheel is identical.
Comments, solutions...?
Greetings, Andrej