[MrBoxx]

The flapper does indeed not open 90*, so unless you relocate the post on the flapper armature to which the actuator arm connects, it won't open any further than it does now, ported or not. I ported mine before I knew that information. It probably didn't hurt anything, but it most likely didn't help anything, either. The guys doing your porting know what they're talking about.

To port to reduce boost creep, focus mainly on the inlet to the wastegate, in the turbine inlet area, opening up a better path to the wastegate opening.