I saved the game again and noticed that it did not create a 52. I played a bit but then noticed something - the autosaves weren't working (I did something and selected the wrong choice in the game so I decided I wanted to load the most recent autosave and try again - it wasn't there).
I plugged the USB back into my Xbox360 and loaded the save. I then went back to modio and I deleted the old 51, and added the modded version of 51. I saved the file to a folder called 'me3 modded' under the same file name. I edited various things but mainly added 9999999 credits.
Then I placed my latest save (51) on the desktop and opened it up with Gibbed. I have that folder currently with all of my original non-corrupted game saves. I took a backup (loaded the profile, selected ME3, selected my career) and did a backup by selecting all of my saves under that profile and then placing them in a folder. I finished ME3 a few times and decided to mod it to make the game fun. Anyone who could shed some light would be appreciated.