(55-48)/2 = 3.5″ of rear tire hanging off each side. It’s not a problem at all. I don’t have side rails. Only a little wood around the front to contain things like crate of spares, fuel jug, and streeter. The front fits between the fenders easy, and the rear end is at the back of the trailer where there are no obstacles. I use the front for items mentioned above. Later last year, we fabbed a rack from steel tubing to double deck and carry 2 machines. Total trailer investment is still <$300.
I can try to post a few pics later. Last June, I was worried about many of the same things you are. Don’t worry about it. This is awesome bang for buck transportation. Maybe consider a nice cover for rainy trips home in the afternoon.