This is how I remove the yellowing found on old plastics. Not my idea, just the result of many internet searches and experiments.
Note: Preventing the paste from drying out is essential, so a good seal is needed!
Note: Preventing the paste from drying out is essential!
The process can take many days to complete. So, be patent and take the time to ensure you have achieved the required results. There is no need to remove it too early.
Wash the parts thoroughly in clean water. Ensure all the peroxide paste has been removed, which can burn, especially when it has dried up and concentrated a bit.