While I was in London shooting for my London Eye pic I kept an eye out for these too. Managed to get this shot by luck spraying and praying as it drove past in Trafalgar Square. Sadly the sky is blown beyond repair but not a lot I can do about that.
I experimented with some partial desats to emphasize the difference between old and new but eventually decided to submit as-is.
Lightroom: RAW conversion, (very minor) crop
PSE5: USM to enhance contrast (except on the headlights which it blew out), resize, sharpen, border, SFW
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