I changed mine, took about 10 minute per wheel and you dont have to take your wheels off.
Like others said, you have to use something like an awl to push the pins in the old rivets through so they pop out.
Buy some extra rivets, I think they are around .40 cents each and if I remeber correct, you need between 8-10 per arch.

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2008 BMW X5 4.8i (E70)
Alpine White, Burl Walnut, Nevada Black, Sport Package, Cold Weather Package,
Premium Package, Technology Package,
Rear Climate Package, iPod adapter