Hi Richard,
I'm a Type 1 - so, like you, have no pancreatic function. Don't worry too much on how you got to this position in terms of how to control it; the main issue with Type 1 and Type 2 diabetes is that Type 2's have some pancreatic function; and as such can have wide differences in what they can do with regards to carbohydrate consumption.
The best book I've read on controlling diabetes and avoiding the myriad complications is Dr. Bernstein's 'Diabetes Solution'. He is a US doctor who advises a very low carb diet.
As you have noticed that is not the advice given by the NHS; but the NHS advice is, in my humble but correct opinion*, nonsense.
I'd go back to your low carb diet, test regularly and try manage your insulin in relation to how much carbs you are eating. Bernstein talks about the 'laws of small numbers' where he essentially says the less carb and the less insulin you take the more predictable the outcome is. He, for instance, advises against injecting in one site more than 7 units of insulin (as I recall).
How much carb you eat will be down to you but I've found that the best control I've achieved is through severely restricting carbohydrates.
Other books you may find useful are 'Think Like A Pancreas' and 'Blood Sugar 101' - both quite American but potentially useful.
Also, read up on old posts here - there is a lot of information.
Good luck with it and welcome to the club :shock:
Dillinger
* I think I stole that phrase from Barry Humphries; it's a wonderful line I think...