I don't see the point of a diabetic going for the gluten free pastas as good quality durum wheat pastas are middle to low GI anyway, typically about 40-45. If you go for wholewheat pastas, they are even slower to release with a GI of 30-35. Remember too, a typical portion of pasta is about 60g - 80g so. Buitoni wholewheat Penne has 66g per 100g so taking 70g as an average portion size, the carbs in a meal is 46g and, as the main meal of the day, that isn't at all bad when you consider that your body needs something like 220g of glucose per day. This is so vital, your brain needs something like 130g, if you eat less that 220g, your body will extract what it needs from it's own stores. You're quite safe with 46g and especially with it being such a low GI food.
When considering foods to eat, it is always a combination of total amount of carbs ingested, ie portionsize plus the carb content
and the type of carbohydrate. The point about low GI is that the release is slow and you need to match the release rate with your own personal insulin response rate. Slower release gives the insulin longer to work on the glucose so although the carbs do get turned into glucose, the blood sugar is less likely to go above the unsafe level. Type 2s all have a different insulin response though, some are much better than others, so you need to test. The graph below is theoretical for someone whose glycaemic reponse is working normally. Most type 2s have an impaired glycaemic response and none of us know how impaired it is, unless we test.
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