Yes, there are a few differences. That's why the price on the real ones get steep.
First, take a look or feel the bottom. It should be flat/smooth. Take a look at these 2 pictures.
wrong- note the ridge in the bottom; even while it's on a car you can reach under and feel this ridge/groove
correct- note the flat bottom; no ridge/groove; take note on the part number #6421970 and the correct location of service decal, pass. side
Now for the more obvious wrong thing without having to touch it.
wrong-the way the snorkels are mounted is different; these have a mounting flange that's on the outside of the air cleaner body
See the way the snorkel meets the body on this one?
here's how it should mount and look
It shouldn't have a service decal in between the snorkels that says "Front" on it. The top was not chrome. It was painted black just like the rest of the air cleaner.