1957 Franklin Body & Equipment Corp. ad from Cuba.

Found in the March 1957 issue of El Automóvil de Cuba, this ad features builds on a 1953 Ford, 1955 Pontiac, Chrysler New Yorker DeLuxe and Chevrolet Panel models. The captions for the New Yorker DeLuxe and and Chevy panel appear to be reversed. Their former factory (demolished) at Franklin Ave. and Dean St. in Brooklyn, NY is now an upscale grocery store called the Food Garden Market.

57 2 El Auto d C Franklin Ambulances 1AX.jpg
The picture on the kindle bluers some of them out. did all of the ambulances have 3 strips in the window etching?
The Galion dump trucks were made by Galion Industries of Galion Ohio. Franklin Body was a truck body builder and would mount the Galion dump bodies along with the lift frame onto the truck chassis.
My former 1963 Chrysler ambulance was sold by Franklin Body but was manufactured by Pinner Coach Company. I suspect that the ambulances pictured above were also manufactured by another body company other than Franklin Body. Both the Chrysler and the Pontiac look like they were made by Pinner Coach and were sold by Franklin Body.
Yes that would be why the etchings are different on them. That ford looks like it has the meteor light on the pillar. If so it was built by economy. It would be the only example of one i have seen.