The B15 really does not suffer as badly as the B14 does out of the factory. The beam is different and moves differently. Stop the beam from moving, you can bend it out to zero toe to help more.
You can also easily bend the beam with the wheels mounted to the beam, using a high-pressure air jack (looks like a big bar). Place the air jack on the forward facing parts of the wheels and slowly increase pressure. Since this is being done cold, the beam will spring back once pressure is relieved so the force would need to bend the beam out of the spec in which you desire. I take no responsibility if you take my comments and hurt yourself. Understand what pressures and forces you are dealing with before making a silly decision.
You can also easily bend the beam with the wheels mounted to the beam, using a high-pressure air jack (looks like a big bar). Place the air jack on the forward facing parts of the wheels and slowly increase pressure. Since this is being done cold, the beam will spring back once pressure is relieved so the force would need to bend the beam out of the spec in which you desire. I take no responsibility if you take my comments and hurt yourself. Understand what pressures and forces you are dealing with before making a silly decision.