1928 Reo Speedwagon

Your observations on frames is interesting. The rear "shackle" sound much like what they use on the Mack Camelback suspension. On that, the leaf spring ends are on the axle, with the center riding on a trunnion stantion , so single point mount on the frame.
Sometime I'll have to get a picture of my Dart frame, talk about built like a skyscraper, the frame is 3/8" with a deep channel, than an even deeper fishplate front spring to back with a heavy angle at the bottom. All riveted. Rated for over 66,000lbs on 3 axles... in 1951!

Has to be on the top-ten cool automotive truck badges list.
A Rock N Roll band is named after it, come on!

correction, a CRAPPY Rock N Roll band named after it,

Matter of opinion on that one I think, some good songs, some not so good. Now, Iron Butterfly, Grand Funk Railroad, Those were bands!
would have like to see that truck in person.

Grand Funk Railroad was the first concert I ever saw, them with Bloodrock opening for them, 1970 Memphis Coliseum.