I'm sorry, I edited your question rather than reply. I do not think I can fix that.
From my memory, your request was to be able to create an AutoCorrect that would replace any number followed by C with the degree sign and C. Also any number followed by a space and C. You should be able to do this with AutoCorrect, but it will require one AutoCorrect entry for each number without a space and each number with a space. You may also want to do entries with lower case "c."
You noted that this was a University computer. It may be that you use different computers on different days. It is possible to use AutoCorrect backup/restore utilities to save these in a Word document so that you can add them to a different computer. You can find links to these here:
Automated Boilerplate Using Microsoft Word