I clean them with dawn and hot water with a little Clorox bleach added. Rinse well and dry
Boil a pot of water to until your reach 200 degrees Fahrenheit.
Add dye. regulate temp maintaining 200 degrees. Stir dye add plastic parts.
Leave until they take color.
I still have not figured out what is the best length of time, but I usually leave them a min of an hour stirring occasionally.
Not sure if the following step is needed but,
I put cold water in a separate pot and remove dyed parts with tongs and put them in the cold water to cool them off.
Once cold I place them on a paper towel and let dry.