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I'd do that with a laser level and a story pole / stick.
A story pole is a sacrificial bit of straight timber. In this case I'd make it the same length as the console.
Offer the story pole up to the console so that one edge sits exactly over the brackets mark the location of the centres on your pole (ideally at the corner). Once you've done this using a square mark lines across the 2 sides of the pole that meet at the corner. Establish the desired height on the wall with the laser level offer the story pole up to the line and transfer markings onto wall - at this point because the story pole is the same length as the console you can use it to check the exact location. If you don't have a laser level you can tape a spirit level to what would be the underside of the story pole but be aware that if you do this you will have to check and double check the height because it's easy to move shit about without realising it.
Want to mount this console on hallway wall. Is the best method just to measure distance between holes and drill accordingly? Or is there a smarter way? Keen not to fuck this up
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