I am an engineer and work extensively with different metals. My advice would be to modify your existing fork by heating both legs of it near the crown using a blowtorch until they are starting to glow red a little. When the fork legs are hot bend them outwards a little and you will have no risk of cracking the welds.
You would have to repaint the fork afterwards, that is the only disadvantage of the method I am suggesting.
Also, if you use this method. when you have heated the forks and bent them allow them to cool down slowly. Do not quench the heat from them quickly (for example by dipping them in water) or you could make the metal go brittle.