Add the following section under Guidance:

"Step-by-Step Guidance
Refer to the LEED v4 reference guide, with the following modification:

 Existing Fixtures
o Calculations must include existing fixtures. If fixture type or manufacturer cannot be identified, the project team should analyze a new, similar fixture with the same bulb type, wattage, lumen output, and physical design that can be expected to have similar photometric properties."