Clearing Customization of Twenty Twelve Theme

I downloaded twentytwelve for new site I have under construction. Unfortunately, I forgot to make a child theme, and started customizing right away on twentytwelve parent.

I decided that I’d better make a child theme (after I had already customized the parent), and customize the child theme instead, to avoid updates messing up my customization. I followed WP Codex coding to create child team in C-Panel. When I activated the child, it did not take on the style of twentytwelve. I cleared browser cache, deleted my WP Super Cache plug-in, deleted my customized twentytwelve theme, deleted the twentytwelve child theme that hadn’t taken up the style, deleted the child’s style.css file, and started over, from scratch.

However, when I installed a fresh copy of the twentytwelve theme (after all of the purging/deletions), it showed up on my site with all of the previous customizations still intact (even though the caches were emptied)! How do I “clear” the customizations that somehow my WP or C-Panel is remembering from my previous twentytwelve parent installation? Note: I have read the WP Forum notes re others not being able to get the style.css to work for the child, but this is different, I suspect, because I don’t seem to be able to shake off the original customization, and I think that the previously customized twentytwelve parent (which was deleted) must still be in memory somewhere and affecting the creation of a clean, stylized child theme?

I am new to this, would appreciate any help. Thanks very much. My site is messy since I am early in the very early stages of “under construction”, but if it helps I can take off the “cloak”.