On Wed, Nov 6, 2019 at 09:38 AM, Claus Schlund \(HGM\) wrote:

http://www.railfan.net/lists/erielackphoto.cgi?erielack-10-18-19/X7862.jpg

Those are actually truck chassis. The last image, link above, shows just a bare frame behind the firewall, and you can read GENERAL MOTORS TRUCK on the side of the hood.

Dennis Storzek

This group of photos was discussed here recently. 
A key point is that the trucks are NOT loaded on racks, but are supported with individual wooden A-frames and blocking, the pre-rack technology. This link should take you to the original thread:
https://realstmfc.groups.io/g/main/topic/35071473?p=Created,,,20,1,0,0::recentpostdate%2Fsticky,,,20,0,60,35071473
Jack Mullen