Making a reliable C64 power supply

Commodore 64 power supplies are known computer killers. I had a lucky escape with my 35 year old power supply in that it "let the smoke out", and yet the C64 it was powering survived.
It's probably not worth the risk using these power supplies in their original form, so if you're lucky to have one that can be opened (many are potted with epoxy), then this is a simple and cheap way to make sure your power supply is reliable.
Sorry for the camera angles - this was a very quick shoot and edit.

If this saves just one C64, it has been worth it ;-)

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