I think you're talking about the two innermost axles of a six axle diesel. The tighter the curves the more the trucks hang out. There was a "how-to" article I saw somewhere about replacing the blind wheelsets with flanged wheels. I think the writer of the article pressed NWSL 33" wheels onto an axle inside a Plasticstruct piece of tubing, but I don't remember how he fastened it to the truck. Maybe one of our readers can locate the article.