My family originate from Higher Openshaw. They moved to Oldham in the 70s. I'm quite senior in a corporate job now with higher career prospects. I still get the look when people hear my accent.
Being from a working class background just makes you want it more. Use it as a power within you that your blood is a little thicker and tougher than the softer southern folk out there.
Never be embarrassed of your working class background as you make your way in life. That upbringing you have will enable you to converse with people from all levels and get the best out of your team! Study hard constantly ask questions and keep learning - Knowledge is power not accents !