Ouch! Sorry to see that! Well, if you paint the rear, then you will have to paint the front. I think I saw a post before with the X5 M painted front and back along with the wheelwell plus the sideskirt. All silver -- for some reason I didn't think it looked good on a silver. It may be fine with a darker color like black. But that's just me. Although you X would look pretty cool with the 2 tone aerokit. that's what I'd go for.
Since your girlfrield caused the damage to your rear, I'd say you get to hit her rear if you catch my drift
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