no it wont overboost, the solenoid controls that
it just makes the boost more linear, rather than surging.
if you think about it, a boost jet, which is a restrictor, placed in that line will hide some of the pressure from the wastegate, and allow the wastegate to stay closed longer, therefore reaching higher boost.
so removing this restrictor wont increase your boost.
edit: this is all useless with the stock boost solenoid, because that controls the boost in the end.