Two things give it away as a conversion.

The VIN.
The eighth character is a "E". That's a 2.6L engine.

The dash.
Next to the dash dimmer lights, there should be a hand throttle.

Still, it's a well done conversion.

Mitsu # 6 - 98 6G72 Montero Sport, Locking Rear Diff, Aisin Manual Hubs, 31x10.5

Mitsu # 7 - 02 6G74 Montero Limited