Paul Herr (wrench) and Cody McDaniel will both be able to tell you for sure!
Expect Paul along any time now with the info!
Pre USD RS forks are the same (41mm) diameter as the NSR, so they will pop into the NSR yokes (triples). Not 100% sure about the calipers... but I would state Luke's reputation on the fork mounts being threaded; the same as the MC18/21.
"Looking" at the front fender and calipers, they "look" identical to the MC18R5/6K and MC21, but I think the piston sizes are different.
I have all the part numbers if they are of any use.
Andy.
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