Well done, the last three of you are all barking up the right tree. It is indeed for carrying fuel, 500 gallons in each tyre a system called Rolit in trials with RASC in 1961. Can be towed in pairs or singly, airportable & can float.
The were really no clues in the photo about the tow vehicle. Although big seemed to be the expectation it was none other than a Bedford RL. Or did it just happen to be parked there?
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