How can I extract groups of 50 rows and create N polygons with attributes from a text file?

The output feature class based on the sample data should have 3 features (one per file) and 50 columns named and populated from all lines which include the symbol “=”, e.g line 7: LIDAR POINT COUNT=35,391,512, where the ColumnName is "LIDAR POINT COUNT" and the Value is "35,391,512".

The polygon should be created using the UPPER LEFT X, UPPER LEFT Y, LOWER RIGHT X and LOWER RIGHT Y.

The number of features will vary from file to file; another file might result in 312 features.

I have managed to extract the desired rows and aggregate them into the requisite 3 features (see attached 2017 fmw), but am now stuck as to how to pull the attributes back apart and build the polygons...