This T-Slotted crosslide replaces the original Atlas part.  This came in kit form from Metal Lathe Accessories in Pine Grove Mills, PA.  This is one of the best things I've done for this lathe.  Besides being able to place the toolpost or milling attachment at various positions it has been useful for long slotting operations with a slitting saw held in the spindle.  A rear toolpost primarily for cutoff operations is coming up soon.