If you cannot correct the stab mounting problem then I would rather see you set up the elevators to compensate for the roll rather than warp the wings. First off the amount of warp would be very small and hard to do accurately as Rotary suggests. Also by offsetting the elevators to compensate you're keeping the problem and it's correction located at the same place. Warps are speed sensitive and a wing warp to compensate for a stab problem could easily have different effects at different speeds. But unequal elevator settings to compensate for unequal stab angles would keep the effects in close to the center line where they can act on each other in harmony.

But it would be FAR better to fix the problem or send the kit back as defective.