Most 3-point mounted plows, 2-bottom or bigger, need the tractor's wheels set to have roughly 52" between sidewalls. (26" from centerline of tractor to inside of right sidewall) Otherwise, you're adjusting the plow to where it will have a difficult time following with the draft line of the plow on the centerline of the tractor, and still having the furrow side wheel in the furrow. Many compacts have a tough time fitting that criteria. (especially so with wider R4's)
There are single bottom plows made that fit compacts and subcompacts better. And with a single bottom, you can compromise the plows adjustment to fit the tractor's track width and not create a situation where the plow is difficult to pull.
More often than not, a plow will open up a furrow wider than the actual cutting width. It may cut a swath 12", 14", even 16" wide, but it moves that swath of plowed dirt several inches further than it's cutting width. I've plowed literally hundreds of acres with a tractor that has 18.4X30" rear tires and the plow I used was a 3X14". The furrow open furrow usually ended up being 18" to 20" wide. And even if you end up with an open furrow that's an inch or so narrower than tire width, not the end of the world.