From what you describe, it will be a lot easier for you than for those who don’t know any dialect, have no experience with it. Honestly, I do think that it will be easier for you than any other language, if you already know amiyyah. You’d be surprised how you’ll realize that a lot of the words in your dialect match up with words in Fusha. You’ll be fine. Just start at the beginning, and work hard at it daily, and you’ll do great.