Is running a singled dually rim on a trailer a bad idea?

[Lonesome7.3]

I have this old military trailer I am making new again. One of the things I want to do is get rid of the fender well inside the cargo area. I want the sides smooth for more cargo space. I borrowed a dually rim just to move the trailer until I can get my own and I liked the huge cap it crated. As you can see on the other side of the trailer I have a conventional rim and it will not give me the room the tire needs to travel if I smoothed out the cargo area. I heard a long time back that running a single dually rim facing out like that is bad. I doubt I will ever test this trailer’s true load capacity to it limits so does it really matter if I run single dually rims that way?
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