Unlock a page in sections based on levels?

I run a site where members complete challenges in stages. I’d like to unlock the page in sections. For example:

Challenge Page
– Part 1 unlocked for all
– Part 2 displays basic “no access” message if user doesn’t have access.
– Part 3 displays basic “no access” message if user doesn’t have access.
– etc.

I know I could use the More Tag protection to split the page into two parts but I’m hoping to expand a single page into 5+ sections.

I tried using a php insert on the page to pull in the locked content but that seems to override and/or conflict with your basic plugin (I think I could override the errors with jquery but I’d have to know what information to refer to).

Thanks for taking a look at my question!