Pathology slide automation system and method

A slide processing system, comprising:

• a first slide holder configured to hold a plurality of first slides;
• a second slide holder configured to hold a plurality of second slides;
• a first carriage having a first interior cavity, the first interior cavity keyed to an exterior side surface around the first slide holder, the first carriage having a contoured surface corresponding to a first gripping location;
• a second carriage having a second interior cavity, the second interior cavity keyed to an exterior side surface around the second slide holder, wherein a form factor of the first interior cavity is different from a form factor of the second interior cavity, the second carriage having a contoured surface corresponding to a second gripping location;
• and
• a gripper configured to grip the first carriage at the first gripping location and to grip the second carriage at the second gripping location, wherein a contour and location of the first gripping location on the first carriage have a same form factor as a contour and location of the second gripping location on the second carriage.