BLUM Tandem Undermount Drawer Jig

BLUM makes a jig for drilling holes for their Tandem series drawer slides, for example here:

https://www.amazon.com/Blum-Universal-Installation-Template-T65-1600-01/dp/B00C7O6J48

Only problem is they want $55 for that tiny piece of plastic!

This model does the same thing, for a lot less. Only real difference is they use metal guides in the drill holes, so theirs will last longer.