Hey Gorgo I have the 11'2 and carbon paddle as well.
I have already cut the paddle down and glued it using 5min araldite but I found it still too long. So I heated up the area I glued with a hair dryer. This made the glue melt and I could cut more off the shaft. But this time I didnt glue it. I used tape and have been using it for a few months like this now. Sometimes I feel that the length is perfect but other times I reckon I could cut a few more centimetres off.
Just take your time and dont cut too much off at once.
I reckon cut half a centimetre off at a time and use it for a month in different conditions. But having the shaft length at eye level would be the right place in the end. Mine is about 1.5cm still too long. But when your happy, glue it

Hope this helps.