Many year ago, I did a tenant finish in a mall building. The service was fed from the POCO's SDE (Service Distribution Enclosure). The property owner got involved and asked me to coordinate the service connection with the utility and an EC who was also doing TI (Tenant Improvement) in the same building.
If the two EC's could work during the same outage, the other businesses would not be as inconvenienced. However, during the scheduled outage that every customer had been notified about, almost every customer came over and complained to the utility's linemen.
My advice to the OP would be to have the utility turn off the power. Do not work this hot.