Tutorial:::
1. download the software from the link (at the bottom of this page.)
2. Load the mission you want the mods on, 'Save and Quit' then Copy your 'Modern Warfare 2 - Single Player' gamesave from your PS3 to a USB Stick.
3. Plug your USB Stick into your PC, Load up my program. Load SAVEGAME.SVG from your USB Stick (Located Like This)
4. After you have loaded SAVEGAME.SVG you can now use [ADD] or use the [CVARS] button's to modifiyadd CVARS.
5. Once you are happy with the edits, simply [Save SAVEGAME.SVG] and overwrite your existing SAVEGAME.SVG on your USB Stick.
6. Stick your USB Stick back into your PS3. Copy the 'Modern Warfare 2 - Single Player' gamesave back onto your PS3.
7. Load up MW2, Enter Single Player and go on 'Resume Game'.
8. You can EITHER quit the mission and load up Spec-Ops or load up a diffrent mission. NOT ALL THE CVAR'S WILL STAY ENABLED WHEN YOU QUIT!
***this tool is kinda buggy at times but it works***
here the link for the download: just copy and paste to your address bar
http://www.megaupload.com/?d=9TK2GHGL
click here to download