The Bitzenburger has an arrow holder that will work with flat nocks.
It's got an o-ring inside to securly hold the arrow. You bond the first vane, twist the "holder" to the next stop, bond the vane, twist the holder, last vane.

Very easy, no muss...no hand indexing.

Works with moon nocks also..but I modified the vert. bow, arrow holder to work with moon nocks slightly better than the "crossbow" arrow holder.

Mike