Create a Master GCS model and reference the civil (building) model, relative to the GCS coordinates.
Identify the building location by placing a geometry at that location. The geometry is a simple lineart to represent the location of the project. The geometry should be such that the primary and secondary placemark monument points can be identified by snapping.
Create a Project GCS model in which the Master GCS model and the project column grid models will be referenced. The working units of this file should match the working units of the BIM models.
In the Project GCS model reference (coincident) the Master GCS and project BIM model that contains the respective geometry.
Use Define Placemark Monument tool to snap points in each of the models and create placemark monument points. The first placemark monument point should be in the Master GCS and the second in the project geometry which corresponds to the previous placemark point.
Create resulting Azimuthal Equal Area GCS in the Project GCS model — Click the From Placemarks icon in the Geographic Coordinate System Dialog and create a GCS from the monument points just created.
Push/Pull the Project GCS model to the appropriate project files.
The Project GCS model can now be used to push the created GCS to any BIM model that will need to reference geospatial data.
Change the reference settings to use the GCS. You can change the reference orientation of the Master GCS to be Geographic-Reprojected on the Master Alignment model. The model will then rotate to align with the building geometry.
These models can also now be referenced to other models where the geo-referencing orientation options are preferred. To reference models with projected data, select the Orientation to be either "AEC Transform" or "Geographically Re-projected".