This is a dual or single extruder print (2 color) design for a dishwasher clean/dirty indicator.
UPDATED 2/28/2022

DUAL EXTRUDER PRINTING INSTRUCTIONS:

The base part .stl files (clean_dirty_220227b_black_dual.stl and clean_dirty_220227b_white_dual.stl) are for a 2 color dual extruder print 3D printer.

SINGLE EXTRUDER PRINTING INSTRUCTIONS

The base part .stl files (clean_dirty_220227b_black_single.stl and clean_dirty_220227b_white_single.stl) are for single extruder 3D printers.
--- the base file, clean_dirty_220227b_black_single.stl, has been modified to have 0.5 mm gap between the base and letters on all sides.
--- --- The gap was increased in this revision from 0.25 mm to 0.5 mm to allow easier insertion of the letters per several user requests.
--- --- I tested this design and the letters fit easily.

SLIDER PRINTING INSTRUCTIONS:

The slider file (clean_dirty_220227b_slider_25.5.stl) works with either dual or single extruders.
--- File: clean_dirty_220227b_slider_26.stl should only be used if the 25.5 wide slider is too loose for your printer settings.

ASSEMBLY INSTRUCTIONS:

Based on erinsugars comment, I have added the following instructions:

The design is intended to be difficult for the slider to fall out in use. Unfortunately this can make it difficult to insert it into the base.
I installed the slider as follows:
--- position the slider in the middle of the base with one edge inserted in the bottom groove.
insert a flat screwdriver between the top of the slider and the top groove
--- apply just enough force to the screwdriver to allow the points on the slider to slide into the base
--- for this revision I narrowed the slider to 25.5 mm wide (clean_dirty_220227b_slider_25.5.stl)
--- if the 25.5 mm slider is too loose, then I provided a wider slide (clean_dirty_220227b_slider_26.stl)

CREDITS:

This design was inspired by Dishwasher Clean/Dirty Sign, by alexberkowitz August 21, 2017 but does not use any of his files.https://www.thingiverse.com/thing:2494096