Good first step!

Does that mean that (for the remaining pages on the site)...

a.) the other scraped content which exists on the remaining pages will be put in an iframe (rather than as text on the page)

- OR -

b.) that you will be removing nofollow from the pages you are scraping content from?

Either you trust the content enough that you should link to it directly, or you should put it in an iframe such that search engines don't see it. Either route would likely be more akin to fair use than what you are currently doing (automatically scraping 3rd party content into your pages and using it to rank against the content creators, without permission, and without a way of opting out).