I would go to Dodge by default, but that's just because for me that make is more well known.

I'd say that number of units produced/sold is the most important: if there are 5 times more one model than the other, even if not precisely identifiable statistically there are more chance that it is the most sold model.

If sales figures were approximately the same, I do not know which one to pick.
How do people refer to such case in North-America? Is not of the name more common when referencing them? (other than "K-cars" for example)
Or we just pick one or the other by default, as long as we indicate it is "by default" it does not matter much I suppose...

As some car were developed on a photocopy machine and had ( or still have ) many friends , some are identical ( or nearly identical ) and a ' By Default' pops up from time to time when we don't have enough visual info to distinguish them.
Maybe we should decide on a make only http://www.imcdb.org/vehicle.php?id=993830 made me search and find both Reliant & Aries as default while some don't have a default yet like http://www.imcdb.org/vehicle.php?id=994025

How do we choose the Default one ?
By the name the people know them ( for K car the Reliant is the first to my mind but the Aries might be for the rest of us )
By sales ?
By Alphabetical order ?

Maybe we can also list the names chosen by default here too , would be easier to find than looking on each model to find them