an R clasp being 1992 is possible from what I understand, although the 6 is meant to represent the month of production.
It's also likely that the bracelet was just attached later by someone who took the time to source the correct-ish clasp. Many will tell you that if the bracelet is correct to the watch that the clasp being a different code shouldn't matter much and some will say it does. Up to everyone to decide on this personally.
@smithdg13 78360 is correct for a GMT Master, a 2-letter clasp typically indicates it was a rolex service replacement clasp or bracelet.
I will note that the more important matching component when it comes to the bracelet would be the endlinks. 78360's are fitted on explorers, EXII's, GMT's, Daytona's, all of which used different end links.
https://www.bobswatches.com/rolex-serial-numbers
https://watch-collector.co.uk/rolex-...nd-link-codes/