I have a habit of mounting amps and as much other stuff as possible in hidden places. Make the sterio look as stock as possible. Amps I like to remove the plastic interior panels run all wire hidden under the rug and mount the amp somewhere that when the interior is put back in it is behind the panels hidden. It does make it very difficult if you need to work on it. Airflow is also a concern as well as something touching it. Dont know what space you have in a el camino. Speakers I like to get speakers that will fit into stock locations & fit under stock speaker grills. Subs are difficult due to size. The headunits you dont have much choice on they are visible. Just mount them in correctly and securely.
The one car I didnt do the above because my friend insisted we just lay the stuff in. Only had the stereo in it for a day or two before it was stolen along with all of my install tools I had forgotten in the car. Which brings me to dont leave tools in the car. Why make it easier for teh theif.
