Never heard of a 530 with a M5 package. Do you have a 2003 M-sport which has some pieces in common with the M5, but I would never use the term M5 package again to avoid criticism.
Now, WELCOME! You have started a journey that really will change your life. 2003 was the only year that cars that came with the "sport" package received a whole bunch of left over M parts that normally would have only found their way to M5s or in earlier years, FOREIGN "sport" models could have come with the M-sport goodies. Say, if you lived in Germany and bought that 530 in 2001, it was offered with the M-sport package-just not in the US until (and only) 2003. M badgeing, suspension parts, etc. does not reach the level of using a term like 530/M5. Just call it an M-sport, if that is, in fact, what you have.
Please do not succumb to adding dual exhaust, M5 badgeing, etc. to try and make a M5 clone. Without that 390hp, let your car be what it is and that is a beautiful thing! Congrats. You will learn a ton here- some will seem to agree and some will seem to "pick", but generally the intent will be to help you as long as you approach people the right way and do as much homework on your own first (use search function before asking...) and read the stickies. Watch-out for James (Mod), he is a real hard-azz and will make your life miserable, in general. (Only kidding, of course Jaime!!!) Gumbi, James, et al will steer you right always.
You'll have 1000+ posts before you know it. Get your post count up to 25 by adding to other's posts rather than just create useless posts to run your count up, but when you get there we want pix!