I got a co-op 20 years ago and ran with it. Somehow I have ended up at one of the big 4 as SR. Engineer. Is there any reason I should go back to school.
only if you want to, if not just lie and say you got your degree back then. Realistically it is just a perceptions thing.
Maybe look at doing something very specific in your field. Most masters are paid for and won't really look at your undergrad if you are paying.