the DZ called the Dingo will be the one with the pump on the front. and the fuel line going directly from the carb to the head of the engine.

the 140L or 140FZ will both be stamped with 140-FZ on the side of the mounting Lug.

The difference in the 140FZ, and 140L is mostly internal but the 140FZ doesn't have the big nub on the back of the carb for the YS motor mount. The 140L has a different Crank and gets more boost and power from its supercharger system than the 140FZ. The L also a slightly larger bore carb, and a few other little things.

There is a new version of this motor sold currently today and that is the 140FZ _Sport

The Sport is a 140L carb and all the other little mods but has the crank shaft that has less overall boost to the super charger.

The DZ is un-mistakable as it has direct injection fuel injection. If the fuel line goes from the carb up to the head of the engine is a Dingo (DZ). If it has the pump on the front rather than the regulator on the bottom of the engine then its a Dingo (DZ)