Pacer wasn't produced until 1980. Aside from that, I've never seen one (drooled on over a dozen in person, plus pics) that had square
windows. They are all rounded. Additionally, the Pacer's exterior door handle hardware is distinctly different, and the door is molded so that it couldn't just be "replaced" with a different kind of unit without serious modification. Pacer wheelwells are also arched higher and have skirts bolted to the body. Even with the skirts removed, the cutouts are a different shape. Among other things.
But it does have a few things that stand out as being unique to Pacers as well. Ie; lip on the countertop, water filler location.
Not saying it's 100% for sure
Scamp, but I'd eat my hat if the
vin tag says it came from Perris. Interesting though.