It works now!

Hey Rob!  I think it's pretty solid now.  I ended up splitting the HTML, CSS, and JS output into their own files and then linking to them all in the main output.html.  That way, each editor can simply overwrite its own file then reload the main output file (which is never altered) in the iframe.  I figured a debounce couldn't hurt either, especially with large projects.  Let me know what you think.