I didn't see a tut for this anywhere when i was looking for one so heres my own take on it.

You will first need a program called SC Conviction - Save Editor
http://www.mediafire.com/?bal0auu7xbjnaadHere

Now extract Your Profile.sav
Under
E000(Profile ID)/5553080B/0000001
And Open in the editor.


You will now be able edit your
 
- PEC points either by entering the amount you want or by clicking Max for the maximum amount.
- The amount you need to obtain challenges.
Note: It is advised to set the challenges to only require 1. This way you will be able to earn the achievements for the game.







FAQ
Q: I unlocked all of my challenges in this program so why didn't I get the achievements for it?
A: This was feudalnate's response:
Quote
This is why I included the descriptions.
If you simply click complete all and save you won't unlock the achievements for completing each series of challenges.
What you can do is click complete all, go through the list and determine which challenge would be easiest to finish and edit it to have 1 less than the completed amount.
Save, transfer, do the challenge, Achievement Unlocked.


Credit
Me Writing the tutorial
feudalnate for the program.

Also here is a pre-modded save which has