Ok, I may have seen everything MOPAR now...

I wish I had a picture of it, last time I saw it run was 1985 or so.

Several of the images on google show the exact unit, with 6 horns. The one mounted on the tower I worked near had a very visible muffler, about as long as the engine doghouse mounted horizontally about a foot above it. We used to look at the muffler and laugh, figured it was some stupid city code that made them install it.

B.