private void PreviewImage_OnMouseDown(object sender, MouseButtonEventArgs e) {
var list = Car.SkinsManager.EnabledOnly.Select(x => x.PreviewImage).ToList();
var selected = new ImageViewer(list, list.IndexOf(SelectedSkin.PreviewImage))
.ShowDialogInSelectMode();
SelectedSkin = Car.EnabledOnlySkins.ElementAtOrDefault(selected ?? -1) ?? SelectedSkin;
}