Hi, I got myself some lower springs for my Sportif. I've managed to change the front fine and can get the rear struts out of the car, but thats where I hit a wall. I can't get the top mount off to replace the spring. The only way I can see to do it is to undo the nut at the top, which just turns the shock. I've tried gripping the shock through a cloth and again through a bicycle inner tube and each time only ended up scratching the shock a little. A friend has suggested grinding the nut off and finding a replacement, but as both rear struts are doing it meaning I can't just use the other one