If you were here in NJ, I would tell you that you need plans/spec from a NJ Lic PE/EE/Architect first.
Whatever you do, a shut down will be required for the POCO feeds. If the hotel is 'booked' for 5 years, that is a problem, right?
Installation of a new pad mount xfr (with POCO blessing), and set-up of the gen & transfer equipment, and feeders into the existing electric room...may be a thought.
