Thanks, Tom for the reply and for the compasion in your post. In
answer, here's what I have now:

There are four breakers in the outdoor panel - a 60A and a 30A for the
two existing sub-panels inside, a 40A for the A/C, and a 20A (??) for
the shop. There is no more room for any others - at least not
double-pole.

Not sure on the ampacity of the existing service panel as it is very
old and has seen its better days. No lables that I can find. It is
shown (inside cover still on) in the picture link below.

The service is overhead and the meter can is new since Katrina as the
old one was ripped off the side of the house. I bought and installed
it in the days following the storm, but I am not sure of the rating -
but is is brand new. Here's a link to the picture.
http://img.photobucket.com/albums/v4...icalIssues.jpg

The wires from the meter to the panel are new since Katrina as well. I
got the cable from a neighbor who had just recently upgraded his
service to 200A. Not sure on the size, but it is bigger than what I
took out.

As for a trough, there is presently a metal conduit connecting the
meter to the panel. There are also two other unused knockouts on the
bottom of the can and one on each side.

Again, thanks for your help and your recognition of the conditions
here. We've got a looooong way to go, but progress every day is
contributing to success in the long term.