I don't see why you're discussing IR here? I thought the first one is talking about wired steering-wheel controls?

I was but then his response include the URL http://peripheralelectronics.com/images/products/peswi3%20revised%205_01.pdf which talks about connecting the remote to a converter which changes the signal to IR for interfacing with several different types of units. That's how I got confused becuase I would rather do this in a non-IR.

Looks a lot like the Sony Stalk arrangement, in fact. Wonder if it'd plug straight into the tuner module?

That's what I thought but the remote is wired to the wiring harness so you would need to splice the wires into the proper plug for the Sony Stalk then set the values to match the signals which seem to be very different from the Sony signals. I could be wrong tho and we would both have a plug and play solution

Greg