I've seen a number of videos of nuclear flask trains (Bridgwater -> Crewe, for example) being hauled by a 68 and an 88 working together. A search of the forums suggests that 68+88 pairs have been around for a while. These trains eventually find their way to an electrified line, but do they actually change over to electric? Is it possible to drive the pair in electric mode with a driver in the cab of the 68? Here's a video showing them at Walsall definitely still burning oil:
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