Clark Foam was a feature of my childhood – we would drive by it on the way to beach – and my dad would say with some pride that it is where most of the surfboard foam came from.
The factory was on Crown Valley at Forbes. The site may have become a preschool - but it is all gone now and a giant condo complex is there.
https://www.ocregister.com/2012/09/27/preschool-approved-for...
https://www.google.com/maps/@33.5578181,-117.6767446,3a,75y,...