I too have a '71 CS convertible and have been giving this some thought. One solution I've been pondering for the speakers is
- kickpanel speakers, like those sold by YearOne, plus
- what I think are called "Thumpers" that are ~ 6" all-magnet speakers that are basically subwoofers, and mount under the seats (or possibly something like this setup) to provide low base you can really FEEL, and
- rear speakers in the left and right "arm rest" panels to round it all out.
Some time back I heard a system similarly set up, and was impressed with the sound. The key component is the under-the-seat subwoofers, which fill in a lot of what smaller kick panel type speakers cannot do well: the bass frequencies.
Anyone here tinkered with something like this setup, or heard one lately?