If you followed the directions in this thread
https://www.mobileread.com/forums/showthread.php?t=88004
Then all you should have to do is run the uninstalls that you will find in the same zip files you downloaded.
Note after Change log in red
* Jailbreak:
Added an uninstaller, just in case
v0.2.N:
Works on firmware v3.x .
Hope that helps.