You can save a lot of drilling and tapping by using a thread checker plate of the sort often available gratis from suppliers to the craft. I use the one pictured because it contains both inferial NC and NF as well as metric threads. (I've blanked out the name of the company lest I be accused of endorsement.)

Attaching the nuts to the board presents a problem if the thread to be checked is firmly attached to a large structure, e.g. studs on wheels or machinery. Often there isn't enough "swing room" to rotate the board around the stud. I prefer to keep a matching nut on each screw to address this problem. (Sometimes the nuts can interfere with each other so alternating screw/nut pairs are mounted on the back of the plate.)

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