Super six van
Now that I think about it, I believe the van super six air cleaners did not have a decal on the air cleaner lid, but the air cleaners were offset to clear the engine cover. If you get the van post a picture of the air cleaner. If it matches the pasenger car air cleaner then someone added the sSuper Six to the van using passenger car parts and it isn't a factory installation.
Here is the base to a factory B van Super Six air cleaner:
You can see the opening for the carb is clearly offset to clear the engine cover. Because most B vans equipped with a Super Six were built before Dodge put factory cold air intake systems on the air cleaner, I drilled the factory snorkel off the air clenaer and welded on one from a later B van so the air cleaner could use the factory cold air intake system.
Here is a comparison of the factory car and truck Super Six air cleaner with the factory B van Super Six air cleaner:
The B van air cleaner is clearly offset. This is one of only two only B van air cleaners I have ever found and I installed it on my brother's van.