Can I per code add a 50a breaker as in the pic to this existing bus that currently has a 100a breaker that has wire out to a sub-panel in a garage? The new breaker would be connected to this bus with 2x 6awg THHN wires going through the back wall of this panel into conduit and finally into a 6-50r that EVSE (electric vehicle supply equipment) would plug into. This is for a home in San Jose, CA. Service line from meter is 2 awg copper.
2nd question is how to do it. There's no disconnect between the bus and the meter. Do I hire an electrician to do the final hook up onto a live bus or have him decide to turn off power with PGE and pull the meter?