Finally managed to do it - thank you! It certainly wasn't in a hurry to come off!
Managed not to crack the shelf too, so all good
I left on the little plastic attachment that held the wheel and have attached his mineral stone to it (I know lots don't use them but thought I'd get him one anyway). Yodel delivered my Zooplus parcel today when I was at work so missed it! - there's a freestanding 8'' Trixie wheel in that