Comments about UNIVERSAL UNIVERSAL STEERING WHEEL CONTROL BY PAC SWI CAN CAN BUS INTERFACE ADD ON:
Combined with the proper stereo interface and remote, this makes tying into a CAN i/f trivial.
Read all instructions BEFORE you start.
As with the harness i/f and remote i/f, they could all be improved by making a more compact design. Three of these boxes are a lot to try to find room for under the dash.