Hi Dave,
Haha I don't mind! got to be able to take it if you give it
The dreadnought conversion was specifically designed to run on our standard 91. American Petrol is higher than ours as I think as their standard is our super?
But anyways standard and don't think I have noticed a difference using super.... well not that it feels faster etc... never really checked for fuel econmy...
Just treat it as a normal 260, except maybe check the levels of the SC oil and Coolant every couple of weeks, oil is a nightmare as its virtually clear.... The coolant is just your normal stuff.

Best way to check the SC oil level is to use a white kitchen towell (the paper ones) and put the dip stick against that to see where it marks

Hope that helps and feel free to ask any other questions.

Martin.