Another possibility is to use a simple latching circuit connected to a keyboard input on your keywiz (or ipac etc).
Basically, the idea would be this.
1) have (x) latching circuits, each connected to a specific key (say, 1-5 to keep it simple for now).
2) each of your swappable panels has a particular connection wired directly to ground (just like a normal button wireup but without the button).
3) when you Attach the cable for a particular panel, the actual process of plugging in the cable acts like a button push.
4) the prob is that since the cable continues to be connected, the button will continue to be "pushed" which you don't want
5) that's where the latching circuit comes in. basically, you just use a relay, a capacity, and a resistor. When the cable connects it starts charging the capacitor, once the cap is fully charged it fires the relay, which "pushes" the button to the ipac. at that point the cap drains and the relay disconnects and nothing else will happen until you disconnect the cable and start the process all over again.
I'm using a very similar circuit in my cab to convert a knife switch "constant on, constant off" to a push button momentary-on-on-make/momentary-on-on-break type output. Works a treat.
Here's a rough diagram of the circuit. I used a cap and micro relay from radio shack.

NOTE WELL. the drawing includes an LEDWiz, this is ONLY for purposes of supplying a low current 5vdc powersource. You could also get the 5v from a PS rail, a hacked USB cable, etc. As per the ledwiz docs, you wouldn't want to drive an inductive load (like a relay) using the actual LEDWiz outputs.
And, the usual disclaimer. I'm not responsible if you blow up any equipment with this circuit. IWOMD (It worked on my desk)
