Unregistered Users Partial Thread Content

[ChadCLund]

My forum is locked down to members only, so if you are unregistered or a SE bot, you can see the forum thread titles listed, but clicking on a thread takes you to a login page. Which is ok because I do not want unregistered users to read a thread, but this also totally kills search engine crawling.
Is there a way (or plugin) to show only the first part of a thread discussion and then something like "To read more: Please Login or register"?
This way the SE bots have something to feed their...

Read more
Unregistered Users Partial Thread Content

free plugins
minecraft paid for free
mcmarket
mc-market
free minecraft paid plugins
free minecraft plugins
spigotmc
SpigotMC
aac free
ewg free
Minecraft Premium Plugins
ewg free download
litebans free
epicworldgenerator free
free schematics
leaked schematics minecraft
schematics
schematics leaked
schematics free
minecraft schematics free
paid minecraft schematics free
paid minecraft schematics for free
free cracked plugins
free cracked minecraft plugins
plugins
featherboard download
featherboard plugin download
antiaura download
xenforo leaked
xenforo for free
xenforo addons