Very few will get access into this building..some may have seen it detailed before.
Have a look here.. 6 minutes
I remember in about 1993.. Pontiac PR took a bunch of Aussies into a disused cluttered boarded up plant in the old Pontiac manufacturing estate..in a fleet of mini vans with headlamps on (daytime) to see the way ahead inside what had become a monsterous heavy engineering storage facility.. only to arrive at a "squirreled away" as they call it.. internal walled security accessed compound of around 50 saved and concept Pontiac's.. strickly no photos were allowed so it was never able to be recorded... but many of the older Pontiac's particularly and a few Buicks.. were in that compound that are seen now saved in the GMHC.....
https://www.youtube.com/embed/RvVmDsWnMOk