Well shoot, you've got all us researchers here, what are the needed dimensions?
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One of the critical dimensions is depth and I can't tell you that
without disassembling the cabinet. I did it once so I could reinforce
the back panel to support a television mount on the other side. It
took hours to get everything to fit back together properly.
Can you just probe around it with a piece of wire. Some real stiff
steel leader might work. My favorite is the core of an outboard
shift/throttle cable.