I have several thread gauges.... but as i have only just obtained an OE switch gear (bike didn't have any of them fitted) and it came without screws, i need to establish what they areSuggest you get a thread gauge, only £4 or £5 and takes any guesswork out, especially if a DPO has been working hard to confuse you with non original threads.
Just one example, lots of alternate sources.
https://www.ebay.co.uk/itm/51-BLADE...624015&hash=item1a26d1cfe6:g:2h0AAOSwhlZYt0dm