hmm sounds a bit suss to me that the fuzz would run around in a spec up vehicle like that,
Our local police landys are stock except for one ive seen that has a winch and a Ford Transit 4x4 which actually looks kool as fook.
I would not be surprised if its some **** who has added sirens and lamps to their landy unless of course you saw the tow offices fully kitted out, I know when i was in the RNLI Several people through out the country got fuzzed as they had blue lights and sirens fitted