Generally the fan should be within an inch of the core, a shroud helps but shouldn't be a substitute.

As for the stops, it depends on what the tire will hit if it can swing further, e.g. radius rods, frame, fenders, and so on. Also, will your brake hoses have enough slack to make the arc, and/or not so much as to kink. The stock stops can be turned or ground down to increase travel if the above don't become an issue.