BB I disagree with what you have said
You use washing soda or Soda Ash and no heat needed yes it can take a few hours for the above mower bass about 4hrs for me I have plenty of time
I have been using this method for about 20 years and lots of info on it
My tank set up below also lead is the best anode and you only need one
Ian
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half Number plate took about 2 hrs then jet blasted with water and hand brushed with a brass wire brush

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