How to clean a coolant header tank - Real results on my Land Rover Discovery 2

I purchased a very used BMW E30 coolant header tank to install into my Land Rover Discovery 2. But it's filthy ..... Can I get it clean. This is a genuine video, I did NOT buy a new coolant tank !! See me try various methods to get the tank looking like new!! If this video has helped you please consider buying me a coffee; https://www.buymeacoffee.com/trollman69b