I did it. I was desperate, and it worked. The basic idea here is to convert your ps3 save to an xbox save, edit that save using Gibbed Save Editor, and convert it back to a ps3 save. Don't worry, it's extremely easy. You won't need to hex edit. Make sure to edit a save no later than when you officially arrive on the Normandy again (Right after you meet Samantha). Yes this works on Official Firmware.
EDIT 2: You can edit the game save as early as the first time you get to manually save I believe. Someone should try it. And this works with Mass Effect 2 as well (As long as you use the Mass Effect 2 gibbed save editor, and make sure to use a save ONLY WHEN ON THE NORMANDY)
Things You Will Need (Google is your friend, not sure I can post links here, I'm new >.<):
Gibbed Save Editor
Brute Force Save Data (Aldo Tools)
Your Mass Effect 3 save data (On PS3 of course)
A Usb Flash drive
-You will need to unhide extentions for known file types, to do this on windows, open explorer, Go to Organize > Folder and Search Options > View > and make sure "Hide extensions for known file types" is UNCHECKED.
1.) Copy your Mass Effect 3 save data from your PS3 to your usb. Plug the usb into your PC and copy the save file (It is located in PS3/SAVEDATA/) to your PC, Somewhere you'll remember. I made a folder called "PS3 Saves". Make sure you create a backup of your save file in case anything goes wrong.I made a backup copy in a folder called "PS3 Originals".
2.) Download and install WINRAR on your PC if you don't have it. Download GIBBED save editor, and extract the folder to your desktop.
3.) Download BruteForce Save Data and install it on your PC. Once installed, start up BruteForce Save Data. It will ask you to enter your ps3 id and such, skip that for now. First thing you'll want to do is look for an option at the top called "path for SAVEDATA Folders". The default path is "C:\Program Files\Bruteforce Save Data\" But you should change it to wherever you copied your Mass Effect 3 save file on your pc. (Change it by clicking the "..." on the right side. Next, click refresh, and your Mass Effect 3 save should pop up. Right above the save data in BruteForce, you will see in small writing "Profile (with random characters)". Right-click on it and select "Use Current PARAM.SFO" It will tell you to enter a friendly name. You may enter whatever you like and press "OK".
4.) In the bottom left corner, you should see various files from your ME3 save. select the save you wish to edit. It should say something like "SAVE0001" the numbers at the end will depend on which save it is. For this tutorial I will use "SAVE0001" When your desired save is highlighted, right-click on it and select "Decrypt PFD". You have now decrypted your save.
5.) Now open the folder with your decrypted save, and rename it to an xbox save file. In this case, mines was renamed to "Save_0001.xbsav". Another example, If your save name is "SAVE0008" then rename it "Save_0008.xbsav". After you rename the file, open Gibbed save editor.
6.) In Gibbed save editor, select "open" at the top and choose the xbox sav file. Edit it to your liking. If you're looking for armor, it is located in "Plot > Mass Effect 3 > Armor > Flag". Checking the "debug" box will give you the N7 hoodie, Shepard's romance clothing, and more. If you want your Shepard to have those awesome illusive man eyes, Player > Appearance > Presets > Open from file > Presets > Eye.
7.) When you're finished, select "save" at the top, and now you're going to overwrite the xbox sav file and exit Gibbed. After that, you must rename your xbox save file back to normal. If it was "SAVE0001" originally then rename it "SAVE0001" with no extensions at the end. Press Enter on your keyboard and you will see "if you rename this file a different extension, it may become unusable, do you want to rename it?" Click Yes.
8.) Now go back to BruteForce and click the "refresh" button at the top right. Click on your SAVE file you were editing (in the bottom left box) to highlight it, then right-click and select "Encrypt PFD". Go back to the top of BruteForce, and right-click on the Mass Effect 3 save file, select "Rebuild with current profile (Partial). Select "yes".
And there you have it. Close Bruteforce, copy the save folder to your ps3 via usb. Make sure you load the save you edited. In my case, SAVE0001.