After I had finished fitting the front springs I decided to make my own set. See picture.
My set holds the metal cup with the spring in one movement when removing.
The threaded bar is M16. The hooks are made from 6mm steel and do not bend. The smaller hook on the end is welded to the bar so won't move. The larger hook fits inside the cup. It's impossible for it to slip out as its the correct depth for the cup.
If you position it correctly, you can squash the spring easily and remove it safely.