Correct you are..as seen in this Maserati vid @ the 3:00 minute mark...No because it's a late MC with (I think the centre exit exhaust?) which may need a different X-pipe. Certainly that is a different under tray from any car I've seen which would probably be a function of the age.
@xDennis is it the exhaust in the centre a la Euro Stradale? Eurospares should be able to confirm if the OEM centre muffler is interchangeable on the earlier ones, and thus, if your un-silenced unit will fit
Although it looks like the other join is under that plastic:
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228235 appears to be universal so your first job will be the undertray. However, I reserve the right to be totally wrong