I believe that, despite firewalling, for a 2-unit structure the D/C's should be in one location.

Usually single drop and D/C exemptions are only allowed on really BIG structures (5K+ ft2 each) serving different occupants in our area.

The 2 meter/main to 2 subpanels is probably going to be your answer. Hopefully you can convert the existing panel without too much trouble.

[This message has been edited by DougW (edited 08-28-2004).]