My RetroSound Radio Install

You can get single, and double din black plastic boxes that can be mounted under your dash. I have a double din I'm going to put in my 66 B-Cuda, with a Sony unit with satelite radio. My add-on gages will bolt to the bottom of it. Sat antenna will be mounted magnetcally on trunk, for easy removal, when parked some where. They are not expensive, and are not plastic per say, just some strong plastic looking stuff. They also have different kinds of add on pieces for them also. Boxes are available from "Sonic Electronix", or Crutchfeild. Two companys make them.
Hope this helps
Dave