Just changed mine at the weekend , the top 4 on the engine at any rate.
They prise open exactly as Grockle describes , but I would like to add : as fitted the main loop has very small tabs to hold the loop closed.
On three of them I could simply prise open the main loop , but on one I had to open the small holding down tab before I could get the main loop open. Maybe doesnt apply to other , but until I noticed it I couldnt get the clip to open.
