So I started with a P320c in .357 SIG and I picked up a .40 barrel for it. If I decide to stay with the .40 barrel, I need to change the sights, correct? My current sights are both #8s. If I stay with .40, I believe I would need to go with a #6 front sight and #8 rear. Please let me know if I am on the right track. Thanks, as always, for any input!