[Shotimes] rear spoiler mounting

[van Oss]

Can anyone please help me with sources or tips?  I'm about to install a Gen2 rear spoiler on a Gen1 trunk lid.

My question has to do with locating the holes in the trunk lid.  I semi-recall (maybe it was an eBay auction, maybe a vendor site)
reading about a neat trick for accurately placing the hole centers.  The key was a plastic strap, maybe a foot long or so, about the
width and thickness of a cable tie.  In the center was a round prong.

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You put the prong into the threaded hole on the underside of the spoiler.  The ends of the strap stick out from under the spoiler.
You lay the spoiler on the trunk lid, position as desired, tape down the straps, lift off the spoiler, and voila, the prongs are now
placed where you need to drill holes.

Anyone know where I can obtain such locating straps?

Joseph van Oss