I fitted mine, it's not difficult. Get a piece of string and clip it in to each end of the site skirt and use that as a guide. Pull it tight, the line should be roughly where you want to place the bottom of the stripe.
Apply slowly using a credit card. Think it took me no longer than an hour to do both sides.
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DRIVE SENSIBLY
Kill your speed in resedential areas
And give peeps more time to admire your ride!