When it comes to the N-Series, what other N-classes can some cars be tuned to?

[MIE1992]

Like, if an event permits tuning, I recall hearing that various N-series cars can be tuned up or down to fit in an N-class they don't originally belong to. So for example, the BMW M4 and Alfa Romeo 4C can both be tuned respectively from N400 and N200 to N300. Were there other examples of this? Like can something like a Bugatti Veyron be tuned down to N900, or could one of the N100 cars be tuned up to N200?