Do you have to have a special mag for a raised cam motor?

No, but it will need raised the amount of the raised cam height (.390" for most if not all). I made a spacer out of 3/8" aluminum plate and it seems to work just fine.

If you have an MSD mag, the gear height is adjustable. Just make sure that you don't obstruct the oil flow to the top end or you will burn up your valve train.