If I am understanding your comment above that "as long as the reticle is level, does not matter if gun has a cant" this is not true.
A bullet leaves the barrel in a straight line, BUT that straight line must be up through the line of sight. For a normal 100 yard zero and a scope center 1.5" above the bore, that means the bullet intercepts the scope center line of sight TWICE. Once at 25-28 yards and again at 100 yards as gravity is pulling it straight down back through the line of sight. If your reticle is level, but the gun is canted, that means the bore line is off angle with the scope line of sight. If canted to the left, the straight line of the bore is going left, and it will NEVER come back. Can you "zero" this rifle? Yes, for that one distance, but if you shoot past 100, your bullet will be way left. To have a long range accurate gun, your reticle HAS to be perfectly level to a perfectly level bore.