Ok guys, the 3mm ceramic balls are a slightly smaller size ball but never the less do fit but do not slot in unlike the original size. they feel nice as well when all attached.
Only issue is the thrust race as the associated B4 thrust race doesnt fit and is way too big so now need to work out what ceramic thrust I can get thats not wider than 1.3mm.
Still good news my latest design rear gearbox CF sides are perfect so have now finished that totally. Im now working on the pivot blocks.
