In order to remove the rivets, they need to be driven or drilled out from the inside of the slide. To access, you will have to remove the entire bolt head, safety, and then the carrier assembly.
Congratulations on the acquisition--- send it to James @Marine0303!!! :biggrin:I just got myself a P9S and I notice the rear sights appear to be fixed in place by two pins. How exactly are they held in place? Thanks.
Holy moly--- you're right--- good catch!!! :biggrin:8+ year delay on your response @AGG , but what the hell?