We haven't run across one of these unique cabinets before, and decided to bring it on back with us.
The Diagnosis Cabinet was built around 1948-1951 and allowed the mechanic to tuck away their Sun Test equipment. It came with a writing desk in the center and a top illuminated glass display. We love the curved cast metal end caps. Below is the original catalog ad from 1950.
This is not a small unit. Measuring in at 13 feet wide, 17 inches deep, and 7 and a half feet tall. Here is cabinet as found in its original mechanics garage.