Our lt-15m came with some collet chucks we will not use. So we are on the hunt for Kitagawa's that came with it. The tag calls for a b208 and a n208. I know that the b is a thru hole chuck and the n is a closed hole. But, can we use the more commonly availiable open (used market) b208 on both spindles? Is there a different clamping cylnder on the closed spindle?