I came across this company looking into dizzys for my 2.6- they make electronic units, one of which can be tuned via USB on a laptop!
They sell a 4 cylinder and 6 cylinder unit for Lucas replacements, but are both are pretty expensive. I doubt the cost is justified and it goes against the simplicity of a rover, but I know some want to wring every last bit of go juice out of their mill.

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