That looks great! How much clearance do you have at the fork and chainstays? I am interested because I want to cram some 40’s onto my cross bike too but it looks like there will only be 1/8" clearance on either side of the tire.
Fork is set up normally, it just has a reverse arch (manitou minute). Purpose of the reverse arch is that the arch can be designed shorter with the same tire and mud clearance as a standard arch. So you get a stiffer fork with zero weight penalty.