Bodies were almost all the same on these. There's a shot in Rebel Rodz this month of one like this on air bags. Local club here in Denver had a newer step van on air until an arsonist burned it.
My first job out of high school in 1967 was working in a factory that built these. We called them bread trucks. I worked in the paint shop. It was loud crappy work, but I learned a lot. They were built on Ford or Chevy chassis. This is an IH. Can't remember if we built any of these. It was all riveted together.