no idea where you're getting this crap about cutting strut mounts and i don't even know what a camber plate is, but that is bullshit and forget it
as old matey said, there is adjustable bushes or you can get adjustable arms
i'm guess you're talking about cutting the top off the strut so you can put s13 style camber tops on top of the shock?
R32 and all skyline suspension do not rely on the top of the shock to adjust camber.
maybe you should talk to a mechanic that has a clue, cause no offence but you sound like you know nothing about the car and i'd hate to see you post a thread saying "i've taken an oxy torch to my strut tower, what do i do?"