greetings.

28 should fit without too much messing, make sure you get the 28 linkage with the swing arm as the 18 one won't fit.

rvf and nc30 swingarms have an offset shock tunnel so won't fit the 18 without loads of cutting and welding.

nc24 swing arm is ok. on the one i've got i've used nc24 swing arm with nc30 hub and mc28 linkage. it a bit pick and mix but the nc24 swingarm was ony £20.
hope some of this helps