WP4NUV

Just curious here. I have a 2015 CMax hybrid whose APIM died apparently. No BT, no voice, no USB. Finding a replacement has been crazy because of the different types out there. My radio and sync are the same as the OP and I have looked up in Crutchfield all the parts required. My question is more about the Maestro Rr. I know its to keep steering wheel controls, but it seems a lot just to keep those. Its not a replacement APIM, right? What other functions do these extras add to this project? Vehicle info? Has anyone tried to hook up into the existing microphone or the temp sensor cabling?, even if its a "patch" job? Reason I ask is that I saw a photo of someone's finished work; looks just like the OP's but the temps matched (top 4 inch and new unit). I hope all that makes sense.. let me know if there are any other info.