Firstly, I did not say that the cars sold by John were sold as anything other than what they were - I said the cars were converted to Mini K spec, not converted into Mini Ks. That is an important distinction. I do not believe John would have sold the cars as anything other than what they were.
Secondly, the image of the police Mini in Issue 17 letters page seems to be causing a bit confusion as well, though not really surprising.
Here is the entire photo, as it was sent to me. As you can see, the front of the car is missing from the original photo. It was also received as fairly low resolution, but was quite suitable for the small use in the magazine.
There are a few interesting points about this car that do require clarification, but not all questions can be answered.
The car is clearly a square-fronted car, not a round-nose, so the square taillights are correct for the car.
The twin tanks are interesting, particularly as the car does not have wheel arch flares and has standard rims with hubcaps. There are no GT stripes, but it appears all (or at least most) police Clubman GTs were supplied without stripes, so this doesn't give anything away.
Looking closely at the interior it appears the top dash rail is painted, rather than padded.
The boot badge is rectangular, as per the Clubman series, and cannot be read, but the shortness of it suggests it would be Mini 1100, rather than Mini Clubman or Clubman GT.
The sun visor would have been either fitted by the police garage or by the dealership - by this time Larke Hoskins was the primary supplier of Minis to NSW Police.
There is an interesting small door mirror quite low down. Again, this would have been fitted either by the dealership or the police.
I would suggest this car is a base model Mini 1100 with twin fuel tanks. The right-hand tank would have been either fitted by the dealership or the police garage.
SPO27 was the Special Production Option for police specification Minis (non Clubman GT), and lists oil gauge, temperature indicator and handbrake warning light. By this time, reversing lights were standard, as they were required by ADR 1 from 1 January 1972.
Neither the sun-visor, the right-hand tank or the external mirror were listed as part of SPO 27. It is difficult to decipher from the SPO list (found Leyland publication PUB 1052) but it would seem that the station cars came with the oval binnacle of the Mini K or with the Mini Clubman (two-gauge) dashboard plus an oil gauge.
However, getting back to the original question - this car is not a Mini K, so is really not relevant.
Cheers,