M16 caliper dust boot retaining clips

[scudderfish]

Is there any special technique to fitting them other than a large amount of swearing? One of mine is loose and I can't see an easy way of getting it on.

[unstable load]

This is just a thought, as I need to do my Landy calipers, but don't they need to be fitted out of the body and then installed with the piston?
That's the situation for me, as I went out and bought just the dust covers and there is no way I can see they will fit with the pistons in place.