My sincere compliments as well, Alex.
I spent about three hours on this puzzle, convinced it had something to do with a Funeral Procession in South Asia or Africa or any country where elephants were more or less "revered".
I never considered the US, particularly as the towing vehicle had very small wheels and a very small frontal area looking more like a European car.
Especially bad on my part as I did a lot of work with Gillig when I was employed by SAAB-Scania USA and Scania started looking into exporting bus chassis to the US and they were a candidate for building the bodies. I was not interested in the history of
busses at the time so did not spend any time looking at their historical archives, which they offered. As my responsibility was Spare Parts, I was only interested in their service level for replacement parts and their warranty policy.
One of my many "lost opportunities" during my thirty year automotive career. Too many times I did not see the forest for the trees as my interests did not match my opportunities.
Good job Alex..........
Bill