Modifications:

• Base parts STACKABLE.

• There is a base for 4x small drawers

• There is a base for 2x large drawers

• There is a double-wide base for 4x small drawers and 2x large drawers

• There is a double-wide base for 4x large drawers
  The standard width bases stack onto the double-wide bases.

UPDATE 17Jan2019: Added small and large draws without separators. Thinking about a locking plate for the back - need to do some tests.