I'd love that. Alternatively, pop that Tom's shirt onto a red jacket Pertwee!
I'm shocked this hasn't happened. Paint the shirt piece white, Give it a cloak with purple lining, and that's a must-buy Pertwee variant.
With a bit of effort not too hard, but you might want to check over at CaptainJimiPie’s YouTube channel. He’s probably done a video.
It depends on the figure, the newer ones tend to have removable heads, but if not then it's probably a boil and pop method.
i'm boring now
I'll second boil and pop. Put the figure in a bowl and fill the bowl with boiling water. Let it sit for a while. The hot water will make the plastic more pliable. Then slowly pull and twist back and forth on the head until it eventually pops out.