Hi all, a friend of mine recently bought a used rock shox ride dual crown. Currently he is running a marzocchi drop off 2 on a Mongoose black diamond double. The drop off does not have a race on top of the crown as it is made to support the bearing without one. The question is, when he puts his new fork on, does it make a difference what race he gets as long as it is 1-1/8" to fit the steerer?

P.S. he has an external bottom bearing shaped like a disk 1cm or so in height.