I am king!
Okay, after weeks of looking, I've figured it out!
I use FACEBOX plug in. So make sure to have that installed.
1. Strip single.php in your theme file of all headers and sidebars. (I am not sure if it is necessary but I could not do it until I did that). The point is to simplify the posts so they can load in facebox.
2. Go to functions.php and find `function new_excerpt_more($more)
{
return '<span class="read-more"><a href="' . get_permalink($post->ID) . '">Read More</a></span>';
}`
Yours might look different, but that is basically where wordpress generates the "read more" links for your posts (or links to your posts).
3. Add rel="facebox" to that code:`function new_excerpt_more($more)
{
return '<span class="read-more"><a rel="facebox" href="' . get_permalink($post->ID) . '">Read More</a></span>';
}`