Trying to add audio controls for my 2017 350 with the 4.2 screen no nav. When I ordered the truck we thought it was in the package,but when it came in it wasn’t on the truck. I was pissed! The dealer said because I had both rear cameras it was dropped from the build. I’ve gathered some information on the upgrade and it looks like it mite be something that I can do if I can get all the parts. Any input would be appreciated,