Originally Posted by
rustyus
Just gotta remember the above item(s) come with new ball studs with M3 threads.
I've compared the B4 and B6 front arms, and the B4 outer pivots are wider (15.9mm) than the B6 (14.9mm). It might be possible to use the B6 caster & steering blocks with 0.5mm hub spacers. It might even be possible to use the B6 arms altogether, but I'll have to experiment with that.
Also, since I'm planning on keeping the vintage purple RPM ball cups, I've found they work with both metric and standard ball studs.