Carbon can't rust??? And it's carrier is a rubber boot. (that can't rust either)
Are you talking about the stainless ring, and the driveshaft??
If you are... the stainless rings is supported by O-rings, so any surface rust shouldn't hold it. BUT... the O-rings get hard, and basically glue the stainless ring in place. SO... spary a little penetrating oil under it... and use a wood block and a small pry bar. You will get it to slide.
Oh... and if you use heat... you will cook the O-rings. And... if they melt... it will really be glued in place.